Glucagon-like peptide 1 (glp-1) receptor modulators and uses thereof in regulating blood glucose levels

ABSTRACT

The present disclosure provides novel glucagon-like peptide-1 (GLP-1) receptor modulators such as compounds of Formula (I) or (II), and pharmaceutically acceptable salts thereof. The present disclosure also provides pharmaceutical compositions, kits, and uses that involve the GLP-1 receptor modulators for regulating blood glucose levels and/or treating diabetes via, e.g., modulating the endogenous signaling pathways mediated by the GLP-1 receptor.

RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119(e) to U.S.provisional patent applications, 61/827,674, filed May 27, 2013 and61/839,870, filed Jun. 27, 2013, the entire content of each of which isincorporated by reference herein.

BACKGROUND

Type II diabetes is characterized by decrease in peripheral tissueresponse to insulin in association with impaired cell function, whichresults in increase in fasting glycemia (1,2). Currentlyantihyperglycemic drugs such as metformin, sulfonylureas, orthiazolidinediones have been prescribed to promote insulin secretion orenhance insulin sensitivity, these drugs do not target all of thesymptoms of type II DM (3,4). In cretin hormones (e.g., glucagon-likepeptide-1 (GLP-1) and gastric inhibitory polypeptide GIP) areintestinally derived hormones that stimulate cAMP production via theircognate receptors in pancreatic b cells and subsequently leads toglucose dependent insulin secretion in response to food intake, play animportant role in glucose homeostasis (5). Apart from its insulinotropiceffects, GLP-1 also preserves pancreatic cells, suppresses glucagonrelease, reduces hepatic gluconeogenesis, it delays gastric emptying,reduces food intake by promoting satiety and reveals a favorablecardiometabolic profile (6-9). GLP-1 also displays extra-pancreaticeffects, notably targeting the brain, immune system and heart, where itplays a role in neuroprotection (10-13), regulating immune responses(14-16) and cardioprotection (17-19). All these physiological actions ofGLP-1 are mediated via interaction with its cognate G-protein coupledreceptor—GLP-1 receptor on the target tissues. However, the exactdownstream signaling of these extra-pancreatic physiological actions ofGLP-1 still needed further investigation.

GPCR (G protein-coupled receptor) signaling machinery was onceconsidered as operating in an one-dimensional way, now has been provedto signal through several distinct mechanisms including those mediatedby G proteins and by G-protein independent multifunctional adaptorproteins β-arrestins. In addition to heterotrimeric G proteins, twoprotein families specifically interact with the majority of GPCRs intheir activated conformation: G protein-coupled receptor kinases (GRKs)and β-arrestins (20). GRKs and β-arrestins are considered to be Gprotein-independent signal transducers (20-22). In particular,(3-arrestins act as multifunctional scaffolds that interact with manyprotein partners (23) and protein kinases, thereby leading to thephosphorylation of numerous intracellular targets (24). Distinctselective coupling pathway will elicit quite distinct physiologicoutcome and this finding has currently impacted further on thedevelopment of assay technology and search for pathway selective GPCRdrug (25-28). Indeed, multi-pathway screening of against u-opioidreceptor (29) and agonist for parathyroid hormone receptor (25) lead todiscovery of compounds that provide therapeutic effect without theadverse side effects normally associated with these receptors, supportthe notion that pathway selective (biased) agonists may identify newclasses of therapeutic agents that have fewer side effects. Though theinsulinotropic effect of GLP-1 is mediated by stimulating cAMPgeneration in pancreatic cells via coupling to Gαs, other effects ofGLP-1 have been shown to be mediated via coupling to β-arrestin. GLP-1anti-apoptotic effect on pancreatic β-cells has been shown to bemediated by phosphorylating the pro-apoptotic protein Bad throughβ-arrestin1 dependent ERK1/2 activation (30). β-Arrestin1-mediatedrecruitment of c-Src is involved in proliferative action of GLP-1 onpancreatic β-cells (31). It will be interesting to know otherextrapancreatic function of GLP-1 will be also mediated by arrestincoupling and it will be more straightforward to use pathway selectivecompounds to correlate cellular responses to specific signaling pathway.However, pathway selective compound is rarely available for GLP-1receptor signaling.

Current GLP-1 analogue therapeutics requires frequent subcutaneousadministrations, and leads to reduced compliance and high prices indeveloping area. Typically, the plasma level of active GLP-1 is around 5to 10 pM in the basal state, quickly rises to 20 to 50 pM after oralglucose or meal and will slowly declines to basal level over 2 hours(32-34). However, GLP-1 analogue therapeutics usually require tomaintain constantly a supra-physiological level of GLP-1 analogues, thuslead to activating GLP-1 receptors constitutively and may cause severecomplications upon chronic treatment (35-42).

Identification of novel compounds that modulate the endogenous GLP-1receptor signaling pathways can lead to the development of newtherapeutics useful in regulating blood glucose levels, thereby treatingdiabetes or disorders associated with the GLP-1 receptor.

SUMMARY

This present disclosure is based on the discovery of novel GLP-1receptor modulators (e.g., compounds of Formula (I) or (II), as beingcapable of modulating the endogenous glucagon-like peptide-1 (GLP-1)receptor signaling pathways and thus, may be useful in regulating bloodglucose levels and/or treating diabetes and other disorders associatedwith the GLP-1 receptor. Accordingly, the present disclosure featuresGLP-1 receptor modulators such as compounds of Formula (I) or (II), orpharmaceutically acceptable salts thereof, and methods of using suchcompounds for regulating blood glucose levels and/or treating diabetes.

In one aspect, the GLP-1 receptor modulators described herein arecompounds of Formula (I):

and pharmaceutically acceptable salts thereof, wherein:

G_(A) is hydrogen, ═O, ═S, —OR″, —SR″, —N(R″)₂, alkenyl, alkynyl, anamide group, an ester group, a phosphate group, an aldehyde group, anitrile group, an imino group, a ketone group, a thione group, anisonitrile group, an isothiocyanide group, a carbamate group, athiocarbamate group, or a cyclic or acyclic, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 6 carbon atoms, wherein each instance of R″ is independentlyhydrogen, a cyclic or acyclic, saturated or unsaturated, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 16 carbon atoms;

R_(A1), R_(A2), R_(A3), R_(A4), R_(A5), R_(A6), R_(A7), R_(A8), R_(A9),and R_(A10) are each independently hydrogen, halogen, —OR″, —N(R″)₂, acarboxyl group, or a cyclic or acyclic, substituted or unsubstituted,branched or unbranched, (hetero)aliphatic group having 1 to 6 carbons,or R_(A1) and R_(A2) are joined to form ═O, or R_(A3) and R_(A4) arejoined to form alkenyl;

R_(A11), R_(A13), R_(A15), and R_(A17) are each independently hydrogen,halogen, or a cyclic or acyclic, substituted or unsubstituted, branchedor unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms;

R_(A12), R_(A14), and R_(A16) are each independently halogen, —N(R″)₂,—SR″, —OR″, alkyl, alkenyl, alkynyl, an amide group, a carboxyl group,an ester group, an aldehyde group, a nitrile group, an imino group, aketone group, a thione group, an isonitrile group, an isothiocyanidegroup, a urea group, a carbamate group, or a thiocarbamate group, orR_(A14) and R_(A15) are joined to form ═O or ═S;

R_(A20) is hydrogen, halogen, or a cyclic or acyclic, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 6 carbon atoms; and

R_(A21) is hydrogen, halogen, —N(R″)₂, —SR″, —OR″, —CH₂OR″, alkenyl,alkynyl, an amide group, a carboxyl group, an ester group, an aldehydegroup, a nitrile group, an imino group, a ketone group, a thione group,an isonitrile group, an isothiocyanide group, a carbamate group, athiocarbamate group, or a cyclic or acyclic, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 6 carbon atoms.

All compounds described herein include the compounds themselves, as wellas their salts and stereoisomers, if applicable. The salts, for example,can be formed between a positively charged substituent (e.g., amino) ona compound and an anion. Suitable anions include, but are not limitedto, chloride, bromide, iodide, sulfate, nitrate, phosphate, citrate,methanesulfonate, trifluoroacetate, and acetate. Likewise, a negativelycharged substituent (e.g., carboxylate) on a compound can form a saltwith a cation. Suitable cations include, but are not limited to, sodiumion, potassium ion, magnesium ion, calcium ion, and an ammonium cationsuch as teteramethylammonium ion.

In certain embodiments, a salt described herein is a pharmaceuticallyacceptable salt. The term “pharmaceutically acceptable salt” refers tothose salts which are, within the scope of sound medical judgment,suitable for use in contact with the tissues of a subject (e.g., a humanor non-human animal) without undue toxicity, irritation, allergicresponse and the like, and are commensurate with a reasonablebenefit/risk ratio. Pharmaceutically acceptable salts are well known inthe art. For example, Berge et al., describe pharmaceutically acceptablesalts in detail in J. Pharmaceutical Sciences, 1977, 66, 1-19,incorporated herein by reference. Pharmaceutically acceptable salts ofthe compounds described herein include those derived from suitableinorganic and organic acids and bases. In certain embodiments, apharmaceutically acceptable salt can be a salt described herein.

Compounds described herein can comprise one or more asymmetric centers,and thus can exist in various isomeric forms, e.g., enantiomers and/ordiastereomers. For example, the compounds described herein can be in theform of an individual enantiomer, diastereomer or geometric isomer, orcan be in the form of a mixture of stereoisomers, including racemicmixtures and mixtures enriched in one or more stereoisomer. Isomers canbe isolated from mixtures by methods known to those skilled in the art,including chiral high pressure liquid chromatography (HPLC) and theformation and crystallization of chiral salts; or preferred isomers canbe prepared by asymmetric syntheses. See, for example, Jacques et al.,Enantiomers, Racemates and Resolutions (Wiley Interscience, New York,1981); Wilen et al., Tetrahedron 33:2725 (1977); Eliel, Stereochemistryof Carbon Compounds (McGraw-Hill, NY, 1962); and Wilen, Tables ofResolving Agents and Optical Resolutions p. 268 (E. L. Eliel, Ed., Univ.of Notre Dame Press, Notre Dame, Ind. 1972). The present disclosureadditionally encompasses compounds described herein as individualisomers substantially free of other isomers, and alternatively, asmixtures of various isomers.

In a formula,

is a single or double bond, and

is absent (and therefore any

substituent attached thereto is also absent) or a single bond.

Unless otherwise specified, a moiety described herein may beunsubstituted or may be substituted (e.g., at least one hydrogen atom ofthe moiety being replaced with a non-hydrogen atom or group). When agroup described herein is substituted, the group may be substituted, asvalency permits, with one or more substituents independently selectedfrom the group consisting of C₁₋₆ alkyl (e.g., unsubstituted C₁₋₆ alkyl(e.g., methyl, ethyl, propyl, or butyl) or substituted C₁₋₆ alkyl (e.g.,—CF₃, —CH₂—CF₃, or —C₂F₅)), —OR^(a1) (e.g., —OH, —OMe, or —OEt),—N(R^(a1))₂ (e.g., —NH₂, —NHMe, or —NMe₂), —SR^(a1) (e.g., —SH or —SMe),═O, ═S, —CHO, —C(═O)N(R^(a1))₂ (e.g., —C(═O)NH₂, —C(═O)NHMe, or—C(═O)NMe₂), —CN, —C(═O)OR^(a1) (e.g., —C(═O)OH, —C(═O)OMe, or—C(═O)OEt), —OC(═O)R^(b1) (e.g., —OC(═O)Me, —OC(═O)Et, or—OC(═O)(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃), —OC(═O)OR^(a1) (e.g., —OC(═O)OMe,—OC(═O)OEt, or —OC(═O)O(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃)),—C(R^(b1))₂OR^(a1) (e.g., —CH₂—OH or —CH₂—OMe), —C(R^(b1))₂SR^(a)1(e.g., —CH₂—SH or —CH₂—SMe), —C(R^(b1))₂N(R^(a1))₂ (e.g., —CH₂—NH₂,—CH₂—NHMe, or —CH₂—NMe₂), and —C(R^(b1))₂C(═O)OR^(a1) (e.g.,—CH₂—OC(═O)OMe, —CH₂—OC(═O)OEt, or—CH₂—OC(═O)O(CH₂)₇CH═CHCH₂CH═CH(CH₂)₄CH₃)), wherein each instance ofR^(a1) is independently H, C₁₋₆ alkyl (e.g., unsubstituted C₁₋₆ alkyl(e.g., methyl, ethyl, propyl, or butyl) or substituted C₁₋₆ alkyl (e.g.,—CF₃, —CH₂—CF₃, or —C₂F₅)), C₂₋₆ alkenyl (e.g., unsubstituted C₂₋₆alkenyl (e.g., vinyl)), 3- to 10-membered cycloalkyl (e.g.,unsubstituted 3- to 10-membered cycloalkyl (e.g., cyclopropyl)), or 6-to 10-membered aryl (e.g., phenyl (e.g., unsubstituted phenyl orsubstituted phenyl)), and each instance of R^(b1) is independently H,halogen (e.g., F, Cl, Br, or I (iodine)), C₁₋₆ alkyl (e.g.,unsubstituted C₁₋₆ alkyl (e.g., methyl, ethyl, propyl, or butyl) orsubstituted C₁₋₆ alkyl (e.g., —CF₃, —CH₂—CF₃, or —C₂F₅)), C₂₋₆ alkenyl(e.g., unsubstituted C₂₋₆ alkenyl (e.g., vinyl)), 3- to 10-memberedcycloalkyl (e.g., unsubstituted 3- to 10-membered cycloalkyl (e.g.,cyclopropyl)), or 6- to 10-membered aryl (e.g., phenyl (e.g.,unsubstituted phenyl or substituted phenyl)).

When a range of values is listed, it is intended to encompass each valueand sub-range within the range. For example “C₁₋₆ alkyl” is intended toencompass, C₁, C₂, C₃, C₄, C₅, C₆, C₁₋₆, C₁₋₅, C₁₋₄, C₁₋₃, C₁₋₂, C₂₋₆,C₂₋₅, C₂₋₄, C₂₋₃, C₃₋₆, C₃₋₅, C₃₋₄, C₄₋₆, C₄₋₅, and C₅₋₆ alkyl.

The term “(hetero)aliphatic” refers to aliphatic or heteroaliphatic. Theterm “aliphatic” refers to alkyl, alkenyl, alkynyl, and carbocyclicgroups. The term “heteroaliphatic” refers to heteroalkyl, heteroalkenyl,heteroalkynyl, and heterocyclic groups.

The term “alkyl” refers to a radical of a straight-chained(“unbranched”) or branched, saturated, hydrocarbon group. In someembodiments, an alkyl group has 1 to 6 carbon atoms (“C₁₋₆ alkyl”).Examples of C₁₋₆ alkyl groups include methyl (C₁), ethyl (C₂), n-propyl(C₃), isopropyl (C₃), n-butyl (C₄), tert-butyl (C₄), sec-butyl (C₄),iso-butyl (C₄), n-pentyl (C₅), 3-pentanyl (C₅), amyl (C₅), neopentyl(C₅), 3-methyl-2-butanyl (C₅), tertiary amyl (C₅), and n-hexyl (C₆).

The term “alkenyl” refers to a radical of a straight-chained or branchedhydrocarbon group having one or more carbon-carbon double bonds (e.g.,1, 2, 3, or 4 double bonds). In some embodiments, an alkenyl group has 2to 6 carbon atoms (“C₂₋₆ alkenyl”). The one or more carbon-carbon doublebonds can be internal (such as in 2-butenyl) or terminal (such as in1-butenyl). Examples of C₂₋₆ alkenyl groups include ethenyl (C₂),1-propenyl (C₃), 2-propenyl (C₃), 1-butenyl (C₄), 2-butenyl (C₄),butadienyl (C₄), pentenyl (C₅), pentadienyl (C₅), and hexenyl (C₆).

The term “alkynyl” refers to a radical of a straight-chained or branchedhydrocarbon group having one or more carbon-carbon triple bonds (e.g.,1, 2, 3, or 4 triple bonds). In some embodiments, an alkynyl group has 2to 6 carbon atoms (“C₂₋₆ alkynyl”). The one or more carbon-carbon triplebonds can be internal (such as in 2-butynyl) or terminal (such as in1-butynyl). Examples of C₂₋₆ alkynyl groups include ethynyl (C₂),1-propynyl (C₃), 2-propynyl (C₃), 1-butynyl (C₄), 2-butynyl (C₄),pentynyl (C₅), and hexynyl (C₆).

“Heteroalkyl” refers to an alkyl group as defined herein which furtherincludes at least one heteroatom (e.g., 1, 2, 3, or 4 heteroatoms)selected from oxygen, nitrogen, or sulfur within (i.e., inserted betweenadjacent carbon atoms of) and/or placed at one or more terminalposition(s) of the parent chain. In some embodiments, a heteroalkylgroup is a saturated group having 1 to 16 carbon atoms and 1 or moreheteroatoms within the parent chain (“heteroC₁₋₁₆ alkyl”). In someembodiments, a heteroalkyl group is a saturated group having 1 to 6carbon atoms and 1 or more heteroatoms within the parent chain(“heteroC₁₋₆ alkyl”). In some embodiments, a heteroalkyl group is asaturated group having 1 to 3 carbon atoms and 1 or more heteroatomswithin the parent chain (“heteroC₁₋₃ alkyl”). Unless otherwisespecified, each instance of a heteroalkyl group is independentlyunsubstituted or substituted with one or more substituents.

“Heteroalkenyl” refers to an alkenyl group as defined herein whichfurther includes at least one heteroatom (e.g., 1, 2, 3, or 4heteroatoms) selected from oxygen, nitrogen, or sulfur within (i.e.,inserted between adjacent carbon atoms of) and/or placed at one or moreterminal position(s) of the parent chain. In some embodiments, aheteroalkenyl group has 2 to 16 carbon atoms, at least one double bond,and 1 or more heteroatoms within the parent chain (“heteroC₂₋₁₆alkenyl”). In some embodiments, a heteroalkenyl group has 2 to 6 carbonatoms, at least one double bond, and 1 or more heteroatoms within theparent chain (“heteroC₂₋₆ alkenyl”). In some embodiments, aheteroalkenyl group has 2 to 3 carbon atoms, at least one double bond,and 1 or more heteroatoms within the parent chain (“heteroC₂₋₃alkenyl”). Unless otherwise specified, each instance of a heteroalkenylgroup is independently unsubstituted or substituted with one or moresubstituents.

“Heteroalkynyl” refers to an alkynyl group as defined herein whichfurther includes at least one heteroatom (e.g., 1, 2, 3, or 4heteroatoms) selected from oxygen, nitrogen, or sulfur within (i.e.,inserted between adjacent carbon atoms of) and/or placed at one or moreterminal position(s) of the parent chain. In some embodiments, aheteroalkynyl group has 2 to 16 carbon atoms, at least one triple bond,and 1 or more heteroatoms within the parent chain (“heteroC₂₋₁₆alkynyl”). In some embodiments, a heteroalkynyl group has 2 to 6 carbonatoms, at least one triple bond, and 1 or more heteroatoms within theparent chain (“heteroC₂₋₆ alkynyl”). In some embodiments, aheteroalkynyl group has 2 to 3 carbon atoms, at least one triple bond,and 1 or more heteroatoms within the parent chain (“heteroC₂₋₃alkynyl”). Unless otherwise specified, each instance of a heteroalkynylgroup is independently unsubstituted or substituted with one or moresubstituents.

“Carbocyclyl,” “carbocycle,” or “carbocyclic” refers to a radical of anon-aromatic cyclic hydrocarbon group having from 3 to 10 ring carbonatoms (“C₃₋₁₀ carbocyclyl”) and zero heteroatoms in the non-aromaticring system. In some embodiments, a carbocyclyl group has 3 to 8 ringcarbon atoms (“C₃₋₈ carbocyclyl”). In some embodiments, a carbocyclylgroup has 3 to 6 ring carbon atoms (“C₃₋₆ carbocyclyl”). In someembodiments, a carbocyclyl group has 3 to 6 ring carbon atoms (“C₃₋₆carbocyclyl”). In some embodiments, a carbocyclyl group has 5 to 10 ringcarbon atoms (“C₅₋₁₀ carbocyclyl”). Exemplary C₃₋₆ carbocyclyl groupsinclude, without limitation, cyclopropyl (C₃), cyclopropenyl (C₃),cyclobutyl (C₄), cyclobutenyl (C₄), cyclopentyl (C₅), cyclopentenyl(C₅), cyclohexyl (C₆), cyclohexenyl (C₆), cyclohexadienyl (C₆), and thelike. Exemplary C₃₋₈ carbocyclyl groups include, without limitation, theaforementioned C₃₋₆ carbocyclyl groups as well as cycloheptyl (C₇),cycloheptenyl (C₇), cycloheptadienyl (C₇), cycloheptatrienyl (C₇),cyclooctyl (C₈), cyclooctenyl (C₈), bicyclo[2.2.1]heptanyl (C₇),bicyclo[2.2.2]octanyl (C₈), and the like. Exemplary C₃₋₁₀ carbocyclylgroups include, without limitation, the aforementioned C₃₋₈ carbocyclylgroups as well as cyclononyl (C₉), cyclononenyl (C₉), cyclodecyl(C₁₋₁₀), cyclodecenyl (C₁₋₁₀), octahydro-1H-indenyl (C₉),decahydronaphthalenyl (C₁₋₁₀), spiro[4.5]decanyl (C₁₋₁₀), and the like.As the foregoing examples illustrate, in certain embodiments, thecarbocyclyl group is either monocyclic (“monocyclic carbocyclyl”) orcontain a fused, bridged. or spiro ring system such as a bicyclic system(“bicyclic carbocyclyl”). Carbocyclyl can be saturated, and saturatedcarbocyclyl is referred to as “cycloalkyl.” In some embodiments,carbocyclyl is a monocyclic, saturated carbocyclyl group having from 3to 10 ring carbon atoms (“C₃₋₁₀ cycloalkyl”). In some embodiments, acycloalkyl group has 3 to 8 ring carbon atoms (“C₃₋₈ cycloalkyl”). Insome embodiments, a cycloalkyl group has 3 to 6 ring carbon atoms (“C₃₋₄cycloalkyl”). In some embodiments, a cycloalkyl group has 5 to 6 ringcarbon atoms (“C₅₋₆ cycloalkyl”). In some embodiments, a cycloalkylgroup has 5 to 10 ring carbon atoms (“C₅₋₁₀ cycloalkyl”). Examples ofC₅₋₄ cycloalkyl groups include cyclopentyl (C₅) and cyclohexyl (C₅).Examples of C₃₋₄ cycloalkyl groups include the aforementionedC₅₄cycloalkyl groups as well as cyclopropyl (C₃) and cyclobutyl (C₄).Examples of C₃₋₈ cycloalkyl groups include the aforementioned C₃₋₄cycloalkyl groups as well as cycloheptyl (C₇) and cyclooctyl (C₈).Unless otherwise specified, each instance of a cycloalkyl group isindependently unsubstituted (an “unsubstituted cycloalkyl”) orsubstituted (a “substituted cycloalkyl”) with one or more substituents.In certain embodiments, the cycloalkyl group is unsubstituted C₃₋₁₀cycloalkyl. In certain embodiments, the cycloalkyl group is substitutedC₃₋₁₀ cycloalkyl. Carbocyclyl can be partially unsaturated. Carbocyclylincluding one or more C═C double bond in the carbocyclic ring isreferred to as “cycloalkenyl.” Carbocyclyl including one or more C≡Ctriple bond in the carbocyclic ring is referred to as “cycloalkynyl.”Carbocyclyl includes aryl. “Carbocyclyl” also includes ring systemswherein the carbocyclic ring, as defined above, is fused with one ormore aryl or heteroaryl groups wherein the point of attachment is on thecarbocyclic ring, and in such instances, the number of carbons continueto designate the number of carbons in the carbocyclic ring system.Unless otherwise specified, each instance of a carbocyclyl group isindependently optionally substituted, i.e., unsubstituted (an“unsubstituted carbocyclyl”) or substituted (a “substitutedcarbocyclyl”) with one or more substituents. In certain embodiments, thecarbocyclyl group is unsubstituted C₃₋₁₀ carbocyclyl. In certainembodiments, the carbocyclyl group is substituted C₃₋₁₀ carbocyclyl.

“Heterocyclyl,” “heterocycle,” or “heterocyclic” refers to a radical ofa 3- to 10-membered non-aromatic ring system having ring carbon atomsand 1 to 4 ring heteroatoms, wherein each heteroatom is independentlyselected from nitrogen, oxygen, sulfur, boron, phosphorus, and silicon(“3-10 membered heterocyclyl”). In heterocyclyl groups that contain oneor more nitrogen atoms, the point of attachment can be a carbon ornitrogen atom, as valency permits. A heterocyclyl group can either bemonocyclic (“monocyclic heterocyclyl”) or a fused, bridged, or spiroring system, such as a bicyclic system (“bicyclic heterocyclyl”), andcan be saturated (“heterocycloalkyl”) or can be partially unsaturated.Heterocyclyl bicyclic ring systems can include one or more heteroatomsin one or both rings. Heterocyclyl includes heteroaryl. Heterocyclylalso includes ring systems wherein the heterocyclic ring, as definedabove, is fused with one or more carbocyclyl groups wherein the point ofattachment is either on the carbocyclyl or heterocyclic ring, or ringsystems wherein the heterocyclic ring, as defined above, is fused withone or more aryl or heteroaryl groups, wherein the point of attachmentis on the heterocyclic ring, and in such instances, the number of ringmembers continue to designate the number of ring members in theheterocyclic ring system. Unless otherwise specified, each instance ofheterocyclyl is independently optionally substituted, i.e.,unsubstituted (an “unsubstituted heterocyclyl”) or substituted (a“substituted heterocyclyl”) with one or more substituents. In certainembodiments, the heterocyclyl group is unsubstituted 3-10 memberedheterocyclyl. In certain embodiments, the heterocyclyl group issubstituted 3-10 membered heterocyclyl.

In some embodiments, a heterocyclyl group is a 5-10 memberednon-aromatic ring system having ring carbon atoms and 1-4 ringheteroatoms, wherein each heteroatom is independently selected fromnitrogen, oxygen, sulfur, boron, phosphorus, and silicon (“5-10 memberedheterocyclyl”). In some embodiments, a heterocyclyl group is a 5-8membered non-aromatic ring system having ring carbon atoms and 1-4 ringheteroatoms, wherein each heteroatom is independently selected fromnitrogen, oxygen, and sulfur (“5-8 membered heterocyclyl”). In someembodiments, a heterocyclyl group is a 5-6 membered non-aromatic ringsystem having ring carbon atoms and 1-4 ring heteroatoms, wherein eachheteroatom is independently selected from nitrogen, oxygen, and sulfur(“5-6 membered heterocyclyl”). In some embodiments, the 5-6 memberedheterocyclyl has 1-3 ring heteroatoms selected from nitrogen, oxygen,and sulfur. In some embodiments, the 5-6 membered heterocyclyl has 1-2ring heteroatoms selected from nitrogen, oxygen, and sulfur. In someembodiments, the 5-6 membered heterocyclyl has one ring heteroatomselected from nitrogen, oxygen, and sulfur.

Exemplary 3-membered heterocyclyl groups containing one heteroatominclude, without limitation, azirdinyl, oxiranyl, and thiiranyl.Exemplary 4-membered heterocyclyl groups containing one heteroatominclude, without limitation, azetidinyl, oxetanyl and thietanyl.Exemplary 5-membered heterocyclyl groups containing one heteroatominclude, without limitation, tetrahydrofuranyl, dihydrofuranyl,tetrahydrothiophenyl, dihydrothiophenyl, pyrrolidinyl, dihydropyrrolyland pyrrolyl-2,5-dione. Exemplary 5-membered heterocyclyl groupscontaining two heteroatoms include, without limitation, dioxolanyl,oxasulfuranyl, disulfuranyl, and oxazolidin-2-one. Exemplary 5-memberedheterocyclyl groups containing three heteroatoms include, withoutlimitation, triazolinyl, oxadiazolinyl, and thiadiazolinyl. Exemplary6-membered heterocyclyl groups containing one heteroatom include,without limitation, piperidinyl, tetrahydropyranyl, dihydropyridinyl,and thianyl. Exemplary 6-membered heterocyclyl groups containing twoheteroatoms include, without limitation, piperazinyl, morpholinyl,dithianyl, and dioxanyl. Exemplary 6-membered heterocyclyl groupscontaining three heteroatoms include, without limitation, triazinanyl.Exemplary 7-membered heterocyclyl groups containing one heteroatominclude, without limitation, azepanyl, oxepanyl and thiepanyl. Exemplary8-membered heterocyclyl groups containing one heteroatom include,without limitation, azocanyl, oxecanyl and thiocanyl. Exemplary5-membered heterocyclyl groups fused to a C₆ aryl ring (also referred toherein as a 5,6-bicyclic heterocyclic ring) include, without limitation,indolinyl, isoindolinyl, dihydrobenzofuranyl, dihydrobenzothienyl,benzoxazolinonyl, and the like. Exemplary 6-membered heterocyclyl groupsfused to an aryl ring (also referred to herein as a 6,6-bicyclicheterocyclic ring) include, without limitation, tetrahydroquinolinyl,tetrahydroisoquinolinyl, and the like.

“Aryl” refers to a radical of a monocyclic or polycyclic (e.g., bicyclicor tricyclic) 4n+2 aromatic ring system (e.g., having 6, 10, or 14 pielectrons shared in a cyclic array) having 6-14 ring carbon atoms andzero heteroatoms provided in the aromatic ring system (“C₆₋₁₄ aryl”). Insome embodiments, an aryl group has six ring carbon atoms (“C₆ aryl”;e.g., phenyl). In some embodiments, an aryl group has ten ring carbonatoms (“C₁₀ aryl”; e.g., naphthyl such as 1-naphthyl and 2-naphthyl). Insome embodiments, an aryl group has fourteen ring carbon atoms (“C₁₄aryl”; e.g., anthracyl). “Aryl” also includes ring systems wherein thearyl ring, as defined above, is fused with one or more carbocyclyl orheterocyclyl groups wherein the radical or point of attachment is on thearyl ring, and in such instances, the number of carbon atoms continue todesignate the number of carbon atoms in the aryl ring system. Unlessotherwise specified, each instance of an aryl group is independentlyoptionally substituted, i.e., unsubstituted (an “unsubstituted aryl”) orsubstituted (a “substituted aryl”) with one or more substituents. Incertain embodiments, the aryl group is unsubstituted C₆₋₁₄ aryl. Incertain embodiments, the aryl group is substituted C₆₋₁₄ aryl.

“Aralkyl” is a subset of alkyl and aryl, as defined herein, and refersto an optionally substituted alkyl group substituted by an optionallysubstituted aryl group. In certain embodiments, the aralkyl isoptionally substituted benzyl. In certain embodiments, the aralkyl isbenzyl. In certain embodiments, the aralkyl is optionally substitutedphenethyl. In certain embodiments, the aralkyl is phenethyl.

“Aralkenyl” is a subset of alkenyl and aryl, as defined herein, andrefers to an optionally substituted alkenyl group substituted by anoptionally substituted aryl group. An example of aralkenyl is styrenyl(i.e., —CH═CHPh).

“Aralkynyl” is a subset of alkynyl and aryl, as defined herein, andrefers to an optionally substituted alkynyl group substituted by anoptionally substituted aryl group.

“Heteroaryl” refers to a radical of a 5-10 membered monocyclic orbicyclic 4n+2 aromatic ring system (e.g., having 6 or 10 pi electronsshared in a cyclic array) having ring carbon atoms and 1-4 ringheteroatoms provided in the aromatic ring system, wherein eachheteroatom is independently selected from nitrogen, oxygen and sulfur(“5-10 membered heteroaryl”). In heteroaryl groups that contain one ormore nitrogen atoms, the point of attachment can be a carbon or nitrogenatom, as valency permits. Heteroaryl bicyclic ring systems can includeone or more heteroatoms in one or both rings. “Heteroaryl” includes ringsystems wherein the heteroaryl ring, as defined above, is fused with oneor more carbocyclyl or heterocyclyl groups wherein the point ofattachment is on the heteroaryl ring, and in such instances, the numberof ring members continue to designate the number of ring members in theheteroaryl ring system. “Heteroaryl” also includes ring systems whereinthe heteroaryl ring, as defined above, is fused with one or more arylgroups wherein the point of attachment is either on the aryl orheteroaryl ring, and in such instances, the number of ring membersdesignates the number of ring members in the fused (aryl/heteroaryl)ring system. Bicyclic heteroaryl groups wherein one ring does notcontain a heteroatom (e.g., indolyl, quinolinyl, carbazolyl, and thelike) the point of attachment can be on either ring, i.e., either thering bearing a heteroatom (e.g., 2-indolyl) or the ring that does notcontain a heteroatom (e.g., 5-indolyl).

In some embodiments, a heteroaryl group is a 5-10 membered aromatic ringsystem having ring carbon atoms and 1-4 ring heteroatoms provided in thearomatic ring system, wherein each heteroatom is independently selectedfrom nitrogen, oxygen, and sulfur (“5-10 membered heteroaryl”). In someembodiments, a heteroaryl group is a 5-8 membered aromatic ring systemhaving ring carbon atoms and 1-4 ring heteroatoms provided in thearomatic ring system, wherein each heteroatom is independently selectedfrom nitrogen, oxygen, and sulfur (“5-8 membered heteroaryl”). In someembodiments, a heteroaryl group is a 5-6 membered aromatic ring systemhaving ring carbon atoms and 1-4 ring heteroatoms provided in thearomatic ring system, wherein each heteroatom is independently selectedfrom nitrogen, oxygen, and sulfur (“5-6 membered heteroaryl”). In someembodiments, the 5-6 membered heteroaryl has 1-3 ring heteroatomsselected from nitrogen, oxygen, and sulfur. In some embodiments, the 5-6membered heteroaryl has 1-2 ring heteroatoms selected from nitrogen,oxygen, and sulfur. In some embodiments, the 5-6 membered heteroaryl has1 ring heteroatom selected from nitrogen, oxygen, and sulfur. Unlessotherwise specified, each instance of a heteroaryl group isindependently optionally substituted, i.e., unsubstituted (an“unsubstituted heteroaryl”) or substituted (a “substituted heteroaryl”)with one or more substituents. In certain embodiments, the heteroarylgroup is unsubstituted 5-14 membered heteroaryl. In certain embodiments,the heteroaryl group is substituted 5-14 membered heteroaryl.

Exemplary 5-membered heteroaryl groups containing one heteroatominclude, without limitation, pyrrolyl, furanyl and thiophenyl. Exemplary5-membered heteroaryl groups containing two heteroatoms include, withoutlimitation, imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, andisothiazolyl. Exemplary 5-membered heteroaryl groups containing threeheteroatoms include, without limitation, triazolyl, oxadiazolyl, andthiadiazolyl. Exemplary 5-membered heteroaryl groups containing fourheteroatoms include, without limitation, tetrazolyl. Exemplary6-membered heteroaryl groups containing one heteroatom include, withoutlimitation, pyridinyl. Exemplary 6-membered heteroaryl groups containingtwo heteroatoms include, without limitation, pyridazinyl, pyrimidinyl,and pyrazinyl. Exemplary 6-membered heteroaryl groups containing threeor four heteroatoms include, without limitation, triazinyl andtetrazinyl, respectively. Exemplary 7-membered heteroaryl groupscontaining one heteroatom include, without limitation, azepinyl,oxepinyl, and thiepinyl. Exemplary 5,6-bicyclic heteroaryl groupsinclude, without limitation, indolyl, isoindolyl, indazolyl,benzotriazolyl, benzothiophenyl, isobenzothiophenyl, benzofuranyl,benzoisofuranyl, benzimidazolyl, benzoxazolyl, benzisoxazolyl,benzoxadiazolyl, benzthiazolyl, benzisothiazolyl, benzthiadiazolyl,indolizinyl, and purinyl. Exemplary 6,6-bicyclic heteroaryl groupsinclude, without limitation, naphthyridinyl, pteridinyl, quinolinyl,isoquinolinyl, cinnolinyl, quinoxalinyl, phthalazinyl, and quinazolinyl.

The term “oxo” refers to the a moiety of the formula: ═O.

The term “amide” or “amide group” refers to a moiety of the formula:—N(R^(pp))C(═O)R^(qq), wherein R^(pp) is a nitrogen atom substituentdescribed herein, and R^(qq) is a carbon atom substituent describedherein.

The term “ester” or “ester group” refers to a moiety of the formula:—C(═O)OR^(rr) or —OC(═O)R^(rr), wherein R^(rr) is an oxygen atomsubstituent described herein.

The term “phosphate” or “phosphate group” refers to a moiety of theformula: —OP(═O)(OR^(oo))₂, wherein each instance of R^(oo) isindependently an oxygen atom substituent described herein or a cationiccounterion.

The term “carboxyl” or “carboxyl group” refers to a moiety of theformula: —C(═O)OH.

The term “aldehyde” or “aldehyde group” refers to a moiety of theformula: —C(═O)H.

The term “thialdehyde” or “thialdehyde group” refers to a moiety of theformula: —C(═S)H.

The term “nitrile” or “nitrile group” refers to a moiety of the formula:—CN or -L-CN, wherein L is substituted or unsubstituted, branched orunbranched, C₁₋₁₆ alkylene; substituted or unsubstituted, branched orunbranched, C₂₋₁₆ alkenylene; or substituted or unsubstituted, branchedor unbranched, C₂₋₁₆ alkynylene.

The term “alcohol,” “alcohol group,” “hydroxyl,” or “hydroxy” refers tothe group —OH. The term “substituted hydroxyl” or “substituted hydroxyl”refers to a hydroxyl group wherein the oxygen atom directly attached tothe parent molecule is substituted with a group other than hydrogen, andincludes groups selected from —OR^(aa), —ON(R^(bb))₂, —OC(═O)SR^(aa),—OC(═O)R^(aa), —OCO₂R^(aa), —OC(═O)N(R^(bb))₂, —OC(═NR^(bb))R^(aa),—OC(═NR^(bb))OR^(aa), —OC(═NR^(bb))N(R^(bb))₂, —OS(═O)R^(aa),—OSO₂R^(aa), —OSi(R^(aa))₃, —OP(R^(cc))₂, —OP(R^(cc))₃, —OP(═O)₂R^(aa),—OP(═O)(R^(aa))₂, —OP(═O)(OR^(cc))₂, —OP(═O)₂N(R^(bb))₂, and—OP(═O)(NR^(bb))₂, wherein R^(aa), R^(bb), and R^(cc) are as definedherein.

The term “amino” or “amino group” refers to a moiety of the formula:—N(R^(ii))₂, wherein each instance of R^(ii) is independently a nitrogenatom substituent described herein, or two instances of R^(ii) areconnected to form substituted or unsubstituted heterocyclyl. In certainembodiments, the amino is unsubstituted amino (i.e., —NH₂). In certainembodiments, the amino is a substituted amino group, wherein at leastone instance of R^(ii) is not hydrogen.

The term “imino” or “imino group” refers to a moiety of the formula:═NR^(ss), wherein R^(ss) is a nitrogen atom substituent describedherein.

The term “ketone” or “ketone group” refers to a moiety of the formula:—C(═O)R^(tt), wherein R^(tt) is a carbon atom substituent describedherein.

The term “thione” or “thione group” refers to a moiety of the formula:—C(═S)R^(uu), wherein R^(uu) is a carbon atom substituent describedherein.

The term “isonitrile” or “isonitrile group” refers to a moiety of theformula: —NC.

The term “isothiocyanide” or “isothiocyanide group” refers to a moietyof the formula: —SNC.

The term “thioate” or “thioate group” refers to a moiety of the formula:—C(═O)SR^(zz) or —C(═S)OR^(jj), wherein R^(zz) is a sulfur atomsubstituent described herein, and R is an oxygen atom substituentdescribed herein.

The term “thioamide” or “thioamide group” refers to a moiety of theformula: —N(R^(mm))C(═S)R^(nn), wherein R^(mm) is a nitrogen atomsubstituent described herein, and R^(nn) is a carbon atom substituentdescribed herein.

The term “dithioate” or “dithioate group” refers to a moiety of theformula: —C(═S)SR^(kk), wherein R^(kk) is a sulfur atom substituentdescribed herein.

The term “isocyanato” or “isocyanato group” refers to a moiety of theformula: —NCO.

The term “isothiocyanato” or “isothiocyanato group” refers to a moietyof the formula: —NCS.

The term “carbamate” or “carbamate group” refers to a moiety of theformula: —N(R^(vv))C(═O)OR^(ww) or —OC(═O)N(R^(vv))₂, wherein eachinstance of R^(vv) is independently a nitrogen atom substituentdescribed herein, and R^(ww) is an oxygen atom substituent describedherein.

The term “urea” or “urea group” refers to a moiety of the formula:—N(R^(zl))C(═O)N(R^(zl))₂, wherein each instance of R^(zl) isindependently a nitrogen atom substituent described herein.

The term “thiocarbamate” or “thiocarbamate group” refers to a moiety ofthe formula: —N(R^(vv))C(═S)OR^(ww) or —OC(═S)N(R^(vv))₂,—N(R^(vv))C(═O)SR^(yy) or —SC(═O)N(R^(vv))₂, wherein each instance ofR^(vv) is independently a nitrogen atom substituent described herein,R^(ww) is an oxygen atom substituent described herein, and R^(yy) is asulfur atom substituent described herein.

“Halo” or “halogen” refers to fluorine (fluoro, F), chlorine (chloro orCl), bromine (bromo or Br), or iodine (iodo or I).

An atom, moiety, or group described herein may be unsubstituted orsubstituted, as valency permits, unless otherwise expressly provided.The term “substituted” refers to that at least one hydrogen present on agroup (e.g., a carbon or nitrogen atom) is replaced with a permissiblesubstituent, e.g., a substituent which upon substitution results in astable compound, e.g., a compound which does not spontaneously undergotransformation such as by rearrangement, cyclization, elimination, orother reaction. Unless otherwise indicated, a “substituted” group has asubstituent at one or more substitutable positions of the group, andwhen more than one position in any given structure is substituted, thesubstituent is either the same or different at each position. The term“substituted” is contemplated to include substitution with allpermissible substituents of organic compounds, any of the substituentsdescribed herein that results in the formation of a stable compound. Thepresent disclosure contemplates any and all such combinations in orderto arrive at a stable compound. For purposes of this disclosure,heteroatoms such as nitrogen may have hydrogen substituents and/or anysuitable substituent as described herein which satisfy the valencies ofthe heteroatoms and results in the formation of a stable moiety. Incertain embodiments, the substituent is a carbon atom substituent. Incertain embodiments, the substituent is a nitrogen atom substituent. Incertain embodiments, the substituent is an oxygen atom substituent. Incertain embodiments, the substituent is a sulfur atom substituent. Incertain embodiments, a substituent may contribute to optical isomerismand/or stereo isomerism of a compound.

Exemplary carbon atom substituents include, but are not limited to,halogen, —CN, —NO₂, —N₃, —SO₂H, —SO₃H, —OH, —OR^(aa), —ON(R^(bb))₂,—N(R^(bb))₂, —N(R^(bb))₃ ⁺X⁻, —N(OR^(cc))R^(bb), —SH, —SR^(aa),—SSR^(cc), —C(═O)R^(aa), —CO₂H, —CHO, —C(OR^(cc))₂, —CO₂R^(aa),—OC(═O)R^(aa), —OCO₂R^(aa), —C(═O)N(R^(bb))₂, —OC(═O)N(R^(bb))₂,—NR^(bb)C(═O)R^(aa), —NR^(bb)CO₂R^(aa), —NR^(bb)C(═O)N(R^(bb))₂,—C(═NR^(bb))R^(aa), —C(═NR^(bb))OR^(aa), —OC(═NR^(bb))R^(aa),—OC(═NR^(bb))OR^(aa), —C(═NR^(bb))N(R^(bb))₂, —OC(═NR^(bb))N(R^(bb))₂,—NR^(bb)C(═NR^(bb))N(R^(bb))₂, —C(═O)NR^(bb)SO₂R^(aa), —NR^(bb)SO₂R—,—SO₂N(R^(bb))₂, —SO₂R^(aa), —SO₂₀₀R^(aa), —OSO₂R^(aa), —S(═O)R^(aa),—OS(═O)R^(aa), —Si(R^(aa))₃, —OSi(R^(aa))₃—C(═S)N(R^(bb))₂,—C(═O)SR^(aa), —C(═S)SR^(aa), —SC(═S)SR^(aa), —SC(═O)SR^(aa),—OC(═O)SR^(aa), —SC(═O)OR^(aa), —SC(═O)R^(aa), —P(═O)₂R^(aa),—OP(═O)₂R^(aa), —P(═O)(R^(aa))₂, —OP(═O)(R^(aa))₂, —OP(═O)(OR^(cc))₂,—P(═O)₂N(R^(bb))₂, —OP(═O)₂N(R^(bb))₂, —P(═O)(NR^(bb))₂,—OP(═O)(NR^(bb))₂, —NR^(bb)P(═O)(OR^(cc))₂, —NR^(bb)P(═O)(NR^(bb))₂,—P(R^(cc))₂, —P(R^(cc))₃, —OP(R^(cc))₂, —OP(R^(cc))₃, —B(R^(aa))₂,—B(OR^(cc))₂, —BR^(aa)(OR^(cc)), C₁₋₁₀ alkyl, C₁₋₁₀ perhaloalkyl, C₂₋₁₀alkenyl, C₂₋₁₀ alkynyl, C₃₋₁₀ carbocyclyl, 3-14 membered heterocyclyl,C₆₋₁₄ aryl, and 5-14 membered heteroaryl, wherein each alkyl, alkenyl,alkynyl, carbocyclyl, heterocyclyl, aryl, and heteroaryl isindependently substituted with 0, 1, 2, 3, 4, or 5 R^(dd) groups; or twogeminal hydrogens on a carbon atom are replaced with the group ═O, ═S,═NN(R^(bb))₂, ═NNR^(bb)C(═O)R^(aa), ═NNR^(bb)C(═O)OR^(aa),═NNR^(bb)S(═O)₂R^(aa), ═NR^(bb), or ═NOR^(cc),

each instance of R^(aa) is, independently, selected from C₁₋₁₀ alkyl,C₁₋₁₀ perhaloalkyl, C₂₋₁₀ alkenyl, C₂₋₁₀ alkynyl, C₃₋₁₀ carbocyclyl,3-14 membered heterocyclyl, C₆₋₁₄ aryl, and 5-14 membered heteroaryl, ortwo R^(aa) groups are joined to form a 3-14 membered heterocyclyl or5-14 membered heteroaryl ring, wherein each alkyl, alkenyl, alkynyl,carbocyclyl, heterocyclyl, aryl, and heteroaryl is independentlysubstituted with 0, 1, 2, 3, 4, or 5 R^(dd) groups;

each instance of R^(bb) is, independently, selected from hydrogen, —OH,—OR^(aa), —N(R^(cc))₂, —CN, —C(═O)R^(aa), —C(═O)N(R^(cc))₂, —CO₂R^(aa),—SO₂R^(aa), —C(═NR^(cc))OR^(aa), —C(═NR^(cc))N(R^(cc))₂, —SO₂N(R^(cc))₂,—SO₂R^(cc), —SO₂OR^(cc), —SOR^(aa), —C(═S)N(R^(cc))₂, —C(═O)SR^(cc),—C(═S)SR^(cc), —P(═O)₂R^(aa), —P(═O)(R^(aa))₂, —P(═O)₂N(R^(cc))₂,—P(═O)(NR^(cc))₂, C₁₋₁₀ alkyl, C₁₋₁₀ perhaloalkyl, C₂₋₁₀ alkenyl, C₂₋₁₀alkynyl, C₃₋₁₀ carbocyclyl, 3-14 membered heterocyclyl, C₆₋₁₄ aryl, and5-14 membered heteroaryl, or two R^(bb) groups are joined to form a 3-14membered heterocyclyl or 5-14 membered heteroaryl ring, wherein eachalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl, and heteroarylis independently substituted with 0, 1, 2, 3, 4, or 5 R^(dd) groups;

each instance of R^(cc) is, independently, selected from hydrogen, C₁₋₁₀alkyl, C₁₋₁₀ perhaloalkyl, C₂₋₁₀ alkenyl, C₂₋₁₀ alkynyl, C₃₋₁₀carbocyclyl, 3-14 membered heterocyclyl, C₆₋₁₄ aryl, and 5-14 memberedheteroaryl, or two R^(cc) groups are joined to form a 3-14 memberedheterocyclyl or 5-14 membered heteroaryl ring, wherein each alkyl,alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl, and heteroaryl isindependently substituted with 0, 1, 2, 3, 4, or 5 R^(dd) groups; eachinstance of R^(dd) is, independently, selected from halogen, —CN, —NO₂,—N₃, —SO₂H, —SO₃H, —OH, —OR^(ee), —ON(R^(ff))₂, —N(R^(ff))₂,—N(R^(ff))₃×, —N(OR^(ee))R^(ff), —SH, —SR^(ee), —SSR^(ee), —C(═O)R^(ee),—CO₂H, —CO₂R^(ee), —OC(═O)R^(ee), —OCO₂R^(ee), —C(═O)N(R^(ff))₂,—OC(═O)N(R^(ff))₂, —NR^(ff)C(═O)R^(ee), —NR^(ff)CO₂R^(ee),—NR^(ff)C(═O)N(R^(ff))₂, —C(═NR^(ff))OR^(ee), —OC(═NR^(ff))R^(ee),—OC(═NR^(ff))OR^(ee), —C(═NR^(ff))N(R^(ff))₂, —OC(═NR^(ff))N(R^(ff))₂,—NR^(ff)C(═NR^(ff))N(R^(ff))₂, —NR^(ff)SO₂R^(ee), —SO₂N(R^(ff))₂,—SO₂R^(ee), —SO₂OR^(ee), —OSO₂R^(ee), —S(═O)R^(ee), —Si(R^(ee))₃,—OSi(R^(ee))₃, —C(═S)N(R^(ff))₂, —C(═O)SR^(ee), —C(═S)SR^(ee),—SC(═S)SR^(ee), —P(═O)₂R^(ee), —P(═O)(R^(ee))₂, —OP(═O)(R^(ee))₂,—OP(═O)(OR^(ee))₂, C₁₋₆ alkyl, C₁₋₆ perhaloalkyl, C₂₋₆ alkenyl, C₂₋₆alkynyl, C₃₋₁₀ carbocyclyl, 3-10 membered heterocyclyl, C₆₋₁₀ aryl, 5-10membered heteroaryl, wherein each alkyl, alkenyl, alkynyl, carbocyclyl,heterocyclyl, aryl, and heteroaryl is independently substituted with 0,1, 2, 3, 4, or 5 R^(gg) groups, or two geminal R^(dd) substituents canbe joined to form ═O or ═S;

each instance of R^(ee) is, independently, selected from C₁₋₆ alkyl, C₁₄perhaloalkyl, C₂₋₆ alkenyl, C₂₋₆ alkynyl, C₃₋₁₀ carbocyclyl, C₆₋₁₀ aryl,3-10 membered heterocyclyl, and 3-10 membered heteroaryl, wherein eachalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl, and heteroarylis independently substituted with 0, 1, 2, 3, 4, or 5 R^(gg) groups;

each instance of R^(ff) is, independently, selected from hydrogen, C₁₋₆alkyl, C₁₋₆ perhaloalkyl, C₂₋₆ alkenyl, C₂₋₆ alkynyl, C₃₋₁₀ carbocyclyl,3-10 membered heterocyclyl, C₆₋₁₀ aryl and 5-10 membered heteroaryl, ortwo R^(ff) groups are joined to form a 3-14 membered heterocyclyl or5-14 membered heteroaryl ring, wherein each alkyl, alkenyl, alkynyl,carbocyclyl, heterocyclyl, aryl, and heteroaryl is independentlysubstituted with 0, 1, 2, 3, 4, or 5 R^(gg) groups; and

each instance of R^(gg) is, independently, halogen, —CN, —NO₂, —N₃,—SO₂H, —SO₃H, —OH, —OC₁₋₆ alkyl, —ON(C₁₋₆ alkyl)₂, —N(C₁₋₆ alkyl)₂,—N(C₁₋₆ alkyl)₃ ⁺X⁻, —NH(C₁₋₆ alkyl)₂ ⁺X⁻, —NH₂(C₁₋₆ alkyl)⁺X⁻, —NH₃⁺X⁻, —N(OC₁ alkyl)(C₁₋₆ alkyl), —N(OH)(C₁₋₆ alkyl), —NH(OH), —SH, —SC₁₋₆alkyl, —SS(C₁₋₆ alkyl), —C(═O)(C₁₋₆ alkyl), —CO₂H, —CO₂(C₁₋₆ alkyl),—OC(═O)(C₁₋₆ alkyl), —OCO₂(C₁₋₆ alkyl), —C(═O)NH₂, —C(═O)N(C₁₋₆ alkyl)₂,—OC(═O)NH(C₁₋₆ alkyl), —NHC(═O)(C₁₋₆ alkyl), —N(C₁₋₆ alkyl)C(═O)(C₁₋₆alkyl), —NHCO₂(C₁₋₆ alkyl), —NHC(═O)N(C₁₋₆ alkyl)₂, —NHC(═O)NH(C₁₋₆alkyl), —NHC(═O)NH₂, —C(═NH)O(C₁₋₆ alkyl), —OC(═NH)(C₁₋₆ alkyl),—OC(═NH)OC₁₋₆ alkyl, —C(═NH)N(C₁₋₆ alkyl)₂, —C(═NH)NH(C₁₋₆ alkyl),—C(═NH)NH₂, —OC(═NH)N(C₁₋₆ alkyl)₂, —OC(NH)NH(C₁₋₆ alkyl), —OC(NH)NH₂,—NHC(NH)N(C₁₋₆ alkyl)₂, —NHC(═NH)NH₂, —NHSO₂(C₁₋₆ alkyl), —SO₂N(C₁₋₆alkyl)₂, —SO₂NH(C₁₋₆ alkyl), —SO₂NH₂, —SO₂C₁₋₆ alkyl, —SO₂OC₁₋₆ alkyl,—OSO₂C₁₋₆ alkyl, —SOC₁₋₆ alkyl, —Si(C₁₋₆ alkyl)₃, —OSi(C₁₋₆alkyl)₃-C(═S)N(C₁₋₆ alkyl)₂, C(═S)NH(C₁₋₆ alkyl), C(═S)NH₂, —C(═O)S(C₁₋₆alkyl), —C(═S)SC₁₋₆ alkyl, —SC(═S)SC₁₋₆ alkyl, —P(═O)₂(C₁₋₆ alkyl),—P(═O)(C₁₋₆ alkyl)₂, —OP(═O)(C₁₋₆ alkyl)₂, —OP(═O)(OC₁₋₆ alkyl)₂, C₁₋₆alkyl, C₁₋₆ perhaloalkyl, C₂₋₆ alkenyl, C₂₋₆ alkynyl, C₃₋₁₀ carbocyclyl,C₆₋₁₀ aryl, 3-10 membered heterocyclyl, 5-10 membered heteroaryl; or twogeminal R^(gg) substituents can be joined to form ═O or ═S; wherein X⁻is a counterion.

A “counterion” or “anionic counterion” is a negatively charged groupassociated with a cationic quaternary amino group in order to maintainelectronic neutrality. Exemplary counterions include halide ions (e.g.,F⁻, Cl⁻, Br⁻, I⁻), NO₃ ⁻, ClO₄ ⁻, OH⁻, H₂PO₄ ⁻, HSO₄ ⁻, sulfonate ions(e.g., methansulfonate, trifluoromethanesulfonate, p-toluenesulfonate,benzenesulfonate, 10-camphor sulfonate, naphthalene-2-sulfonate,naphthalene-1-sulfonic acid-5-sulfonate, ethan-1-sulfonicacid-2-sulfonate, and the like), and carboxylate ions (e.g., acetate,ethanoate, propanoate, benzoate, glycerate, lactate, tartrate, andglycolate).

Nitrogen atoms can be substituted or unsubstituted as valency permits,and include primary, secondary, tertiary, and quarternary nitrogenatoms. Exemplary nitrogen atom substituents include, but are not limitedto, hydrogen, —OH, —OR^(aa), —N(R^(cc))₂, —CN, —C(═O)R^(aa),—C(═O)N(R^(cc))₂, —CO₂R^(aa), —SO₂R^(aa), —C(═NR^(bb))R^(aa),—C(═NR^(cc))OR^(aa), —C(═NR^(cc))N(R^(cc))₂, —SO₂N(R^(cc))₂, —SO₂R^(cc),—SO₂OR^(cc), —SOR^(aa), —C(═S)N(R^(cc))₂, —C(═O)SR^(cc), —C(═S)SR^(cc),—P(═O)₂R^(aa), —P(═O)(R^(aa))₂, —P(═O)₂N(R^(cc))₂, —P(═O)(NR^(cc))₂,C₁₋₁₀ alkyl, C₁₋₁₀ perhaloalkyl, C₂₋₁₀ alkenyl, C₂₋₁₀ alkynyl, C₃₋₁₀carbocyclyl, 3-14 membered heterocyclyl, C₆₋₁₄ aryl, and 5-14 memberedheteroaryl, or two R^(cc) groups attached to a nitrogen atom are joinedto form a 3-14 membered heterocyclyl or 5-14 membered heteroaryl ring,wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl,and heteroaryl is independently substituted with 0, 1, 2, 3, 4, or 5R^(dd) groups, and wherein R^(aa), R^(bb), R^(cc), and R^(dd) are asdefined herein.

In certain embodiments, the substituent present on a nitrogen atom is anitrogen protecting group (also referred to as an amino protectinggroup). Nitrogen protecting groups include, but are not limited to, —OH,—OR^(aa), —N(R^(cc))₂, —C(═O)R^(aa), —C(═O)N(R^(cc))₂, —CO₂R^(aa),—SO₂R^(aa), —C(═NR^(cc))R^(aa), —C(═NR^(cc))OR^(aa),—C(═NR^(cc))N(R^(cc))₂, —SO₂N(R^(cc))₂, —SO₂R^(cc), —SO₂OR^(cc),—SOR^(aa), —C(═S)N(R^(cc))₂, —C(═O)SR^(cc), —C(═S)SR^(cc), C₁₋₁₀ alkyl(e.g., aralkyl, heteroaralkyl), C₂₋₁₀ alkenyl, C₂₋₁₀ alkynyl, C₃₋₁₀carbocyclyl, 3-14 membered heterocyclyl, C₆₋₁₄ aryl, and 5-14 memberedheteroaryl groups, wherein each alkyl, alkenyl, alkynyl, carbocyclyl,heterocyclyl, aralkyl, aryl, and heteroaryl is independently substitutedwith 0, 1, 2, 3, 4, or 5 R^(dd) groups, and wherein R^(aa), R^(bb),R^(cc) and R^(dd) are as defined herein. Nitrogen protecting groups arewell known in the art and include those described in detail inProtecting Groups in Organic Synthesis, T. W. Greene and P. G. M. Wuts,3^(rd) edition, John Wiley & Sons, 1999, incorporated herein byreference.

For example, nitrogen protecting groups include, but are not limited to,formamide, acetamide, chloroacetamide, trichloroacetamide,trifluoroacetamide, phenylacetamide, 3-phenylpropanamide, picolinamide,3-pyridylcarboxamide, N-benzoylphenylalanyl derivative, benzamide,p-phenylbenzamide, o-nitophenylacetamide, o-nitrophenoxyacetamide,acetoacetamide, (N′-dithiobenzyloxyacylamino)acetamide,3-(p-hydroxyphenyl)propanamide, 3-(o-nitrophenyl)propanamide,2-methyl-2-(o-nitrophenoxy)propanamide,2-methyl-2-(o-phenylazophenoxy)propanamide, 4-chlorobutanamide,3-methyl-3-nitrobutanamide, o-nitrocinnamide, N-acetylmethioninederivative, o-nitrobenzamide, and o-(benzoyloxymethyl)benzamide.

Nitrogen protecting groups also include, but are not limited to, methylcarbamate, ethyl carbamante, 9-fluorenylmethyl carbamate (Fmoc),9-(2-sulfo)fluorenylmethyl carbamate, 9-(2,7-dibromo)fluoroenylmethylcarbamate,2,7-di-t-butyl-[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methylcarbamate (DBD-Tmoc), 4-methoxyphenacyl carbamate (Phenoc),2,2,2-trichloroethyl carbamate (Troc), 2-trimethylsilylethyl carbamate(Teoc), 2-phenylethyl carbamate (hZ), 1-(1-adamantyl)-1-methylethylcarbamate (Adpoc), 1,1-dimethyl-2-haloethyl carbamate,1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-BOC),1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBOC),1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc), 2-(2′- and4′-pyridyl)ethyl carbamate (Pyoc), 2-(N,N-dicyclohexylcarboxamido)ethylcarbamate, t-butyl carbamate (BOC), 1-adamantyl carbamate (Adoc), vinylcarbamate (Voc), allyl carbamate (Alloc), 1-isopropylallyl carbamate(Ipaoc), cinnamyl carbamate (Coc), 4-nitrocinnamyl carbamate (Noc),8-quinolyl carbamate, N-hydroxypiperidinyl carbamate, alkyldithiocarbamate, benzyl carbamate (Cbz), p-methoxybenzyl carbamate (Moz),p-nitobenzyl carbamate, p-bromobenzyl carbamate, p-chlorobenzylcarbamate, 2,4-dichlorobenzyl carbamate, 4-methylsulfinylbenzylcarbamate (Msz), 9-anthrylmethyl carbamate, diphenylmethyl carbamate,2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methylcarbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonioethyl carbamate(Peoc), 2-triphenylphosphonioisopropyl carbamate (Ppoc),1,1-dimethyl-2-cyanoethyl carbamate, m-chloro-p-acyloxybenzyl carbamate,p-(dihydroxyboryl)benzyl carbamate, 5-benzisoxazolylmethyl carbamate,2-(trifluoromethyl)-6-chromonylmethyl carbamate (Tcroc), m-nitrophenylcarbamate, 3,5-dimethoxybenzyl carbamate, o-nitrobenzyl carbamate,3,4-dimethoxy-6-nitrobenzyl carbamate, phenyl(o-nitrophenyl)methylcarbamate, t-amyl carbamate, S-benzyl thiocarbamate, p-cyanobenzylcarbamate, cyclobutyl carbamate, cyclohexyl carbamate, cyclopentylcarbamate, cyclopropylmethyl carbamate, p-decyloxybenzyl carbamate,2,2-dimethoxyacylvinyl carbamate, o-(N,N-dimethylcarboxamido)benzylcarbamate, 1,1-dimethyl-3-(N,N-dimethylcarboxamido)propyl carbamate,1,1-dimethylpropynyl carbamate, di(2-pyridyl)methyl carbamate,2-furanylmethyl carbamate, 2-iodoethyl carbamate, isoborynl carbamate,isobutyl carbamate, isonicotinyl carbamate,p-(p′-methoxyphenylazo)benzyl carbamate, 1-methylcyclobutyl carbamate,1-methylcyclohexyl carbamate, 1-methyl-1-cyclopropylmethyl carbamate,1-methyl-1-(3,5-dimethoxyphenyl)ethyl carbamate,1-methyl-1-(p-phenylazophenyl)ethyl carbamate, 1-methyl-1-phenylethylcarbamate, 1-methyl-1-(4-pyridyl)ethyl carbamate, phenyl carbamate,p-(phenylazo)benzyl carbamate, 2,4,6-tri-t-butylphenyl carbamate,4-(trimethylammonium)benzyl carbamate, and 2,4,6-trimethylbenzylcarbamate.

Nitrogen protecting groups further include, but are not limited to,p-toluenesulfonamide (Ts), benzenesulfonamide,2,3,6,-trimethyl-4-methoxybenzenesulfonamide (Mtr),2,4,6-trimethoxybenzenesulfonamide (Mtb),2,6-dimethyl-4-methoxybenzenesulfonamide (Pme),2,3,5,6-tetramethyl-4-methoxybenzenesulfonamide (Mte),4-methoxybenzenesulfonamide (Mbs), 2,4,6-trimethylbenzenesulfonamide(Mts), 2,6-dimethoxy-4-methylbenzenesulfonamide (iMds),2,2,5,7,8-pentamethylchroman-6-sulfonamide (Pmc), methanesulfonamide(Ms), β-trimethylsilylethanesulfonamide (SES), 9-anthracenesulfonamide,4-(4′,8′-dimethoxynaphthylmethyl)benzenesulfonamide (DNMBS),benzylsulfonamide, trifluoromethylsulfonamide, and phenacylsulfonamide.

Other nitrogen protecting groups include, but are not limited to,phenothiazinyl-(10)-acyl derivative, N′-p-toluenesulfonylaminoacylderivative, N′-phenylaminothioacyl derivative, N-benzoylphenylalanylderivative, N-acetylmethionine derivative,4,5-diphenyl-3-oxazolin-2-one, N-phthalimide, N-dithiasuccinimide (Dts),N-2,3-diphenylmaleimide, N-2,5-dimethylpyrrole,N-1,1,4,4-tetramethyldisilylazacyclopentane adduct (STABASE),5-substituted 1,3-dimethyl-1,3,5-triazacyclohexan-2-one, 5-substituted1,3-dibenzyl-1,3,5-triazacyclohexan-2-one, 1-substituted3,5-dinitro-4-pyridone, N-methylamine, N-allylamine,N-[2-(trimethylsilyl)ethoxy]methylamine (SEM), N-3-acetoxypropylamine,N-(1-isopropyl-4-nitro-2-oxo-3-pyroolin-3-yl)amine, quaternary ammoniumsalts, N-benzylamine, N-di(4-methoxyphenyl)methylamine,N-5-dibenzosuberylamine, N-triphenylmethylamine (Tr),N-[(4-methoxyphenyl)diphenylmethyl]amine (MMTr),N-9-phenylfluorenylamine (PhF),N-2,7-dichloro-9-fluorenylmethyleneamine, N-ferrocenylmethylamino (Fcm),N-2-picolylamino N′-oxide, N-1,1-dimethylthiomethyleneamine,N-benzylideneamine, N-p-methoxybenzylideneamine,N-diphenylmethyleneamine, N-[(2-pyridyl)mesityl]methyleneamine,N—(N′,N′-dimethylaminomethylene)amine, N,N′-isopropylidenediamine,N-p-nitrobenzylideneamine, N-salicylideneamine,N-5-chlorosalicylideneamine,N-(5-chloro-2-hydroxyphenyl)phenylmethyleneamine,N-cyclohexylideneamine, N-(5,5-dimethyl-3-oxo-1-cyclohexenyl)amine,N-borane derivative, N-diphenylborinic acid derivative,N-[phenyl(pentaacylchromium- or tungsten)acyl]amine, N-copper chelate,N-zinc chelate, N-nitroamine, N-nitrosoamine, amine N-oxide,diphenylphosphinamide (Dpp), dimethylthiophosphinamide (Mpt),diphenylthiophosphinamide (Ppt), dialkyl phosphoramidates, dibenzylphosphoramidate, diphenyl phosphoramidate, benzenesulfenamide,o-nitrobenzenesulfenamide (Nps), 2,4-dinitrobenzenesulfenamide,pentachlorobenzenesulfenamide, 2-nitro-4-methoxybenzenesulfenamide,triphenylmethylsulfenamide, and 3-nitropyridinesulfenamide (Npys).

Exemplary oxygen atom substituents include, but are not limited to,—R^(aa), —C(═O)SR^(aa), —C(═O)R^(aa), —CO₂R^(aa), —C(═O)N(R^(bb))₂,—C(═NR^(bb))R^(aa), —C(═NR^(bb))OR^(aa), —C(═NR^(bb))N(R^(bb))₂,—S(═O)R^(aa), —SO₂R^(aa), —Si(R^(aa))₃, —P(R^(cc))₂, —P(R^(cc))₃,—P(═O)₂R^(aa), —P(═O)(R^(aa))₂, —P(═O)(OR^(cc))₂, —P(═O)₂N(R^(bb))₂, and—P(═O)(NR^(bb))₂, wherein R^(aa), R^(bb), and R^(cc) are as definedherein. In certain embodiments, the oxygen atom substituent present onan oxygen atom is an oxygen protecting group (also referred to as ahydroxyl protecting group). Oxygen protecting groups are well known inthe art and include those described in detail in Protecting Groups inOrganic Synthesis, T. W. Greene and P. G. M. Wuts, 3^(rd) edition, JohnWiley & Sons, 1999, incorporated herein by reference. Exemplary oxygenprotecting groups include, but are not limited to, methyl,t-butyloxycarbonyl (BOC or Boc), methoxylmethyl (MOM), methylthiomethyl(MTM), t-butylthiomethyl, (phenyldimethylsilyl)methoxymethyl (SMOM),benzyloxymethyl (BOM), p-methoxybenzyloxymethyl (PMBM),(4-methoxyphenoxy)methyl (p-AOM), guaiacolmethyl (GUM), t-butoxymethyl,4-pentenyloxymethyl (POM), siloxymethyl, 2-methoxyethoxymethyl (MEM),2,2,2-trichloroethoxymethyl, bis(2-chloroethoxy)methyl,2-(trimethylsilyl)ethoxymethyl (SEMOR), tetrahydropyranyl (THP),3-bromotetrahydropyranyl, tetrahydrothiopyranyl, 1-methoxycyclohexyl,4-methoxytetrahydropyranyl (MTHP), 4-methoxytetrahydrothiopyranyl,4-methoxytetrahydrothiopyranyl S,S-dioxide,1-[(2-chloro-4-methyl)phenyl]-4-methoxypiperidin-4-yl (CTMP),1,4-dioxan-2-yl, tetrahydrofuranyl, tetrahydrothiofuranyl,2,3,3a,4,5,6,7,7a-octahydro-7,8,8-trimethyl-4,7-methanobenzofuran-2-yl,1-ethoxyethyl, 1-(2-chloroethoxy)ethyl, 1-methyl-1-methoxyethyl,1-methyl-1-benzyloxyethyl, 1-methyl-1-benzyloxy-2-fluoroethyl,2,2,2-trichloroethyl, 2-trimethylsilylethyl, 2-(phenylselenyl)ethyl,t-butyl, allyl, p-chlorophenyl, p-methoxyphenyl, 2,4-dinitrophenyl,benzyl (Bn), p-methoxybenzyl, 3,4-dimethoxybenzyl, o-nitrobenzyl,p-nitrobenzyl, p-halobenzyl, 2,6-dichlorobenzyl, p-cyanobenzyl,p-phenylbenzyl, 2-picolyl, 4-picolyl, 3-methyl-2-picolyl N-oxido,diphenylmethyl, p,p′-dinitrobenzhydryl, 5-dibenzosuberyl,triphenylmethyl, α-naphthyldiphenylmethyl,p-methoxyphenyldiphenylmethyl, di(p-methoxyphenyl)phenylmethyl,tri(p-methoxyphenyl)methyl, 4-(4′-bromophenacyloxyphenyl)diphenylmethyl,4,4′,4″-tris(4,5-dichlorophthalimidophenyl)methyl,4,4′,4″-tris(levulinoyloxyphenyl)methyl,4,4′,4″-tris(benzoyloxyphenyl)methyl,3-(imidazol-1-yl)bis(4′,4″-dimethoxyphenyl)methyl,1,1-bis(4-methoxyphenyl)-1′-pyrenylmethyl, 9-anthryl,9-(9-phenyl)xanthenyl, 9-(9-phenyl-10-oxo)anthryl,1,3-benzodisulfuran-2-yl, benzisothiazolyl S,S-dioxido, trimethylsilyl(TMS), triethylsilyl (TES), triisopropylsilyl (TIPS),dimethylisopropylsilyl (IPDMS), diethylisopropylsilyl (DEIPS),dimethylthexylsilyl, t-butyldimethylsilyl (TBDMS), t-butyldiphenylsilyl(TBDPS), tribenzylsilyl, tri-p-xylylsilyl, triphenylsilyl,diphenylmethylsilyl (DPMS), t-butylmethoxyphenylsilyl (TBMPS), formate,benzoylformate, acetate, chloroacetate, dichloroacetate,trichloroacetate, trifluoroacetate, methoxyacetate,triphenylmethoxyacetate, phenoxyacetate, p-chlorophenoxyacetate,3-phenylpropionate, 4-oxopentanoate (levulinate),4,4-(ethylenedithio)pentanoate (levulinoyldithioacetal), pivaloate,adamantoate, crotonate, 4-methoxycrotonate, benzoate, p-phenylbenzoate,2,4,6-trimethylbenzoate (mesitoate), alkyl methyl carbonate,9-fluorenylmethyl carbonate (Fmoc), alkyl ethyl carbonate, alkyl2,2,2-trichloroethyl carbonate (Troc), 2-(trimethylsilyl)ethyl carbonate(TMSEC), 2-(phenylsulfonyl)ethyl carbonate (Psec),2-(triphenylphosphonio) ethyl carbonate (Peoc), alkyl isobutylcarbonate, alkyl vinyl carbonate alkyl allyl carbonate, alkylp-nitrophenyl carbonate, alkyl benzyl carbonate, alkyl p-methoxybenzylcarbonate, alkyl 3,4-dimethoxybenzyl carbonate, alkyl o-nitrobenzylcarbonate, alkyl p-nitrobenzyl carbonate, alkyl S-benzyl thiocarbonate,4-ethoxy-1-napththyl carbonate, methyl dithiocarbonate, 2-iodobenzoate,4-azidobutyrate, 4-nitro-4-methylpentanoate, o-(dibromomethyl)benzoate,2-formylbenzenesulfonate, 2-(methylthiomethoxy)ethyl,4-(methylthiomethoxy)butyrate, 2-(methylthiomethoxymethyl)benzoate,2,6-dichloro-4-methylphenoxyacetate,2,6-dichloro-4-(1,1,3,3-tetramethylbutyl)phenoxyacetate,2,4-bis(1,1-dimethylpropyl)phenoxyacetate, chlorodiphenylacetate,isobutyrate, monosuccinoate, (E)-2-methyl-2-butenoate,o-(methoxyacyl)benzoate, α-naphthoate, nitrate, alkylN,N,N′,N′-tetramethylphosphorodiamidate, alkyl N-phenylcarbamate,borate, dimethylphosphinothioyl, alkyl 2,4-dinitrophenylsulfenate,sulfate, methanesulfonate (mesylate), benzylsulfonate, and tosylate(Ts).

Exemplary sulfur atom substituents include, but are not limited to,—R^(aa), —C(═O)SR^(aa), —C(═O)R^(aa), —CO₂R^(aa), —C(═O)N(R^(bb))₂,—C(═NR^(bb))R^(aa), —C(═NR^(bb))OR^(aa), —C(═NR^(bb))N(R^(bb))₂,—S(═O)R^(aa), —SO₂R^(aa), —Si(R^(aa))₃, —P(R^(cc))₂, —P(R^(cc))₃,—P(═O)₂R^(aa), —P(═O)(R^(aa))₂, —P(═O)(OR^(cc))₂, —P(═O)₂N(R^(bb))₂, and—P(═O)(NR^(bb))₂, wherein R^(aa), R^(bb), and R^(cc) are as definedherein. In certain embodiments, the sulfur atom substituent present on asulfur atom is a sulfur protecting group (also referred to as a thiolprotecting group). Sulfur protecting groups are well known in the artand include those described in detail in Protecting Groups in OrganicSynthesis, T. W. Greene and P. G. M. Wuts, 3^(rd) edition, John Wiley &Sons, 1999, incorporated herein by reference.

In certain embodiments, G_(A) can be hydrogen, ═O, ═S, —OR″, —SR″,—NR″H, alkenyl, alkynyl, an amide group, an ester group, an aldehydegroup, a nitrile group, an imino group, a ketone group, a thione group,an isonitrile group, an isothiocyanide group, a carbamate group, athiocarbamate group, or a cyclic or acyclic, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 6 carbon atoms, wherein each instance of R″ can be independentlyhydrogen, a cyclic or acyclic, saturated or unsaturated, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 16 carbon atoms;

R_(A1), R_(A2), R_(A3), R_(A4), R_(A5), R_(A6), R_(A7), R_(A8), R_(A9),and R_(A10) can each independently be hydrogen, halogen, or a cyclic oracyclic, substituted or unsubstituted, branched or unbranched,(hetero)aliphatic group having 1 to 6 carbons;

R_(A11), R_(A12), R_(A13), R_(A15), R_(A16), and R_(A17) can eachindependently be hydrogen, halogen, or a cyclic or acyclic, substitutedor unsubstituted, branched or unbranched, (hetero)aliphatic group having1 to 6 carbon atoms;

R_(A14) can be halogen, —NR″H, —SR″, —OR″, alkenyl, alkynyl, an amidegroup, an ester group, an aldehyde group, a nitrile group, an iminogroup, a ketone group, a thione group, an isonitrile group, anisothiocyanide group, a carbamate group, or a thiocarbamate group;

R_(A20) can be hydrogen, halogen, or a cyclic or acyclic, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 6 carbon atoms; and

R_(A21) can be hydrogen, halogen, —NR″H, —SR″, —OR″, alkenyl, alkynyl,an amide group, an ester group, an aldehyde group, a nitrile group, animino group, a ketone group, a thione group, an isonitrile group, anisothiocyanide group, a carbamate group, a thiocarbamate group, or acyclic or acyclic, substituted or unsubstituted, branched or unbranched,(hetero)aliphatic group having 1 to 6 carbon atoms.

In certain embodiments, a compound of Formula (I) can be of Formula(I-A):

In certain embodiments, a compound of Formula (I) can be of the formula:

In certain embodiments, a compound of Formula (I) can be of Formula(I-B):

In certain embodiments, a compound of Formula (I) can be of Formula(I-C):

In certain embodiments, a compound of Formula (I) can be of Formula(I-D):

In certain embodiments, G_(A) can be hydrogen. In certain embodiments,G_(A) can be ═O, ═S, —SR″, —OR″, —N(R″)₂, —OH, —SH, or —NH₂. In certainembodiments, G_(A) can be can be ═O. In certain embodiments, G_(A) canbe —OR″ (e.g., —OH, —O(substituted or unsubstituted C₁₋₆ alkyl), or—OC(═O)(substituted or unsubstituted C₁₋₆ alkyl)). In certainembodiments, G_(A) can be can be ═S. In certain embodiments, G_(A) canbe —SR″ (e.g., —SH). In certain embodiments, G_(A) can be —N(R″)₂, —NHR″(such as —NH(substituted or unsubstituted C₁₋₆ alkyl) or—NHC(═O)(substituted or unsubstituted C₁₋₆ alkyl)), or —NH₂. In certainembodiments, G_(A) can be can be alkenyl (e.g., acyclic, substituted orunsubstituted, C₁₋₆ alkenyl, such as ═CHC(═O)O(substituted orunsubstituted C₁₋₆ alkyl)). In certain embodiments, G_(A) can be can bea phosphate group (e.g., —OP(═O)(acyclic, substituted or unsubstituted,C₁₋₆ alkyl)₂). In certain embodiments, R_(A1) can be hydrogen. Incertain embodiments, R_(A1) can be halogen. In certain embodiments,R_(A1) can be an acyclic, substituted or unsubstituted, branched orunbranched, aliphatic group having 1 to 6 carbons (e.g., acyclic,substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl (suchas —CF₃)). In certain embodiments, R_(A1) can be —OR″ (e.g., —OH). Incertain embodiments, R_(A1) can be —N(R″)₂ (e.g., —NMe₂). In certainembodiments, R_(A2) can be hydrogen. In certain embodiments, R_(A1) andR_(A2) can be joined to form ═O. In certain embodiments, R_(A3) can behydrogen. In certain embodiments, R_(A3) can be acyclic, substituted orunsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g., methyl, —CF₃,—CH₂Br, —CH₂OH, —CH₂OC(═O)(substituted or unsubstituted C₁₋₆ alkyl), orethyl). In certain embodiments, R_(A3) can be carboxyl. In certainembodiments, R_(A4) can be hydrogen. In certain embodiments, R_(A4) canbe acyclic, substituted or unsubstituted, branched or unbranched, C₁₋₆alkyl (e.g., methyl, —CF₃, —CH₂C(═O)(substituted or unsubstituted C₁₋₆alkyl), or ethyl). In certain embodiments, R_(A3) and R_(A4) can bejoined to form alkenyl (e.g., ═CH₂). In certain embodiments, R_(A5) canbe hydrogen. In certain embodiments, R_(A5) can be acyclic, substitutedor unsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g., methyl or—CH₂OCF₃). In certain embodiments, R_(A5) cannot be hydrogen. In certainembodiments, R_(A6) can be acyclic, substituted or unsubstituted,branched or unbranched, C₁₋₆ alkyl (e.g., methyl, ethyl, —CH₂OH,—CH₂C(═O)Me, or —CH₂C(═S)Me). In certain embodiments, R_(A6) cannot be—CH₃. In certain embodiments, R_(A7) can be hydrogen. In certainembodiments, R_(A7) can be acyclic, substituted or unsubstituted,branched or unbranched, C₁₋₆ alkyl (e.g., methyl). In certainembodiments, R_(A7) can be —OR″ (e.g., —OH). In certain embodiments,R_(A8) can be hydrogen. In certain embodiments, R_(A8) can be acyclic,substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g.,methyl). In certain embodiments, at least one of R_(A7) and R_(A8)cannot be hydrogen. In certain embodiments, R_(A9) can be hydrogen. Incertain embodiments, R_(A9) can be acyclic, substituted orunsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g., methyl). Incertain embodiments, R_(A10) can be hydrogen. In certain embodiments, atleast one of R_(A9) and R_(A10) cannot be hydrogen. In certainembodiments, R_(A11) can be hydrogen. In certain embodiments, R_(A12)can be hydrogen. In certain embodiments, R_(A12) can be an amino group(e.g., —N(R″)₂, —NHR″, or —NH₂). In certain embodiments,

R_(A13) is absent. In certain embodiments, at least one of R_(A12) andR_(A13) cannot be hydrogen. In certain embodiments, R_(A14) can behalogen, —NR″H, —SR″, —OR″, alkenyl, alkynyl, an amide group, a carboxylgroup, an ester group, an aldehyde group, a nitrile group, an iminogroup, a ketone group, a thione group, an isonitrile group, anisothiocyanide group, a carbamate group, or a thiocarbamate group. Incertain embodiments, R_(A14) can be hydrogen. In certain embodiments,R_(A14) can be alkyl (e.g., acyclic, substituted or unsubstituted,branched or unbranched, C₁₋₆ alkyl (e.g., —CH₂CF₃, —CH₂OR″ (such as—CH₂OH), —CH₂SR″ (such as —CH₂SH), —CH₂N(R″)₂ (such as —CH₂NHMe or—CH₂NH₂), —CH₂C(═O)(acyclic, substituted or unsubstituted, branched orunbranched, C₁₋₂₀ aliphatic (such as

or —CH₂C(═O)N(R″)₂ (such as —CH₂C(═O)NH(substituted or unsubstitutedC₁₋₆ alkyl))). In certain embodiments, R_(A14) cannot be —CH₂OH. Incertain embodiments, R_(A14) can be a carboxyl group. In certainembodiments, R_(A14) can be an ester group (e.g., —C(═O)O(acyclic,substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl), suchas —C(═O)OMe). In certain embodiments, R_(A14) can be an aldehyde group.In certain embodiments, R_(A14) can be a ketone group (e.g.,—C(═O)-(acyclic, substituted or unsubstituted, branched or unbranched,C₁₋₆ alkyl), such as —C(═O)Me). In certain embodiments, R_(A14) can be aurea group (e.g., —NHC(═O)—NH(substituted or unsubstituted phenyl), suchas —NHC(═O)—NHPh). In certain embodiments,

R_(A15) can be absent. In certain embodiments, R_(A14) and R_(A15) canbe joined to form ═O or ═S. In certain embodiments, R_(A16) can behydrogen. In certain embodiments, R_(A16) can be a carbamate group(e.g., —NHC(═O)O(acyclic, substituted or unsubstituted, branched orunbranched, C₁₋₆ alkyl), such as —NHC(═O)OEt). In certain embodiments,R_(A17) can be hydrogen. In certain embodiments, at least one of R_(A16)and R_(A17) cannot be hydrogen. In certain embodiments, R_(A20) can behydrogen. In certain embodiments,

R_(A20) can be absent. In certain embodiments, R_(A21) can be hydrogen.In certain embodiments, R_(A21) can be a cyclic or acyclic, substitutedor unsubstituted, branched or unbranched, (hetero)aliphatic group having1 to 6 carbon atoms. In certain embodiments, R_(A21) can be acyclic,substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g.,—CH₂OR″ (such as —CH₂OH, —CH₂C(═O)OMe, or —CH₂C(═O)(acyclic, substitutedor unsubstituted, branched or unbranched, C₁₋₂₀ aliphatic (such as

—CH₂SR″ (such as —CH₂SH); —CH₂SC(═O)(substituted or unsubstitutedphenyl); or —CH₂N(R″)₂ (such as —CH₂NHR″ (e.g., —CH₂NHMe) or —CH₂NH₂)).In certain embodiments, R_(A21) can be acyclic, substituted orunsubstituted, branched or unbranched, C₂₋₆ alkenyl (e.g., —CH═CHCH₃ or—CH═NBn). In certain embodiments, R_(A21) can be an aldehyde group. Incertain embodiments, R_(A21) can be a carboxyl group. In certainembodiments, each instance of R″ can independently be hydrogen. Incertain embodiments, each instance of R″ can independently be acyclic,substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g.,methyl, ethyl, propyl, or butyl).

The tricyclic ring system

of Formula (I) may include substituents in addition to one or more ofR_(A1) to R_(A17), R_(A20) to R_(A21), and G_(A), as valency permits. Incertain embodiments, the tricyclic ring system of Formula (I) canfurther be substituted at one or two of the positions marked with “*”:

In certain embodiments, the tricyclic ring system of Formula (I) canfurther be substituted with one or more substituents independentlyselected from the group consisting of halogen; substituted andunsubstituted C₁₋₆ aliphatic (e.g., unsubstituted C₁₋₆ alkyl, such as—CH₃); and —OR″ (e.g., —OH).

In certain embodiments, at least one of R_(A1), R_(A2), R_(A5), R_(A7),R_(A8), R_(A9), R_(A10), R_(A11), R_(A12), R_(A13), R_(A15), R_(A16),and R_(A17) cannot be hydrogen. In certain embodiments, at least one ofR_(A3), R_(A4), and R_(A6) cannot be —CH₃. In certain embodiments, whenR_(A21) is —CHO and G_(A) is —OH or ═O, each of R_(A14) and R_(A15)cannot be —CHO.

In certain embodiments, the compound of Formula (I) cannot be of theformula:

wherein:

G_(A) is —OR″ or —N(R″)₂;

R_(A14) is an amide group, a nitrile group, an ester group, orsubstituted methyl; and

R_(A21) is an aldehyde group, —CH₂OR″, or an ester group.

In another aspect, the GLP-1 receptor modulators described herein arecompounds of Formula (II):

and pharmaceutically acceptable salts thereof, wherein:

G is hydrogen, ═O, ═S, —NR′H, —SR′, or —OR′, wherein R′ is hydrogen, anester group, a ketone group, a thione group, or a cyclic or acyclic,saturated or unsaturated, substituted or unsubstituted, branched orunbranched, (hetero)aliphatic group having 1 to 16 carbon atoms;

W is —O—, —S— or —NR′—;

X and Y are each independently a single bond or a saturated orunsaturated, substituted or unsubstituted, branched or unbranched,(hetero)aliphatic group having 1 to 3 carbon atoms;

R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₂ and R₁₃ are each independentlyhydrogen, halogen, or a cyclic or acyclic, substituted or unsubstituted,branched or unbranched, (hetero)aliphatic group having 1 to 6 carbonatoms, or R₂ and R₃ may join to form cycloalkyl, heterocycloalkyl, aryl,or heteroaryl;

R₁₀ and R₁₁ are each independently hydrogen, halogen, an amino group, anamide group, an ester group, an aldehyde group, a nitrile, an iminogroup, a ketone group, a thione group, an isonitrile group, anisothiocyanide group, a carbamate group, a thiocarbamate group, or acyclic or acyclic, saturated or unsaturated, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having 1to 6 carbon atoms;

R₁₄ is hydrogen or a saturated or unsaturated, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having1-16 carbon atoms;

R₁₅ is hydrogen or a saturated or unsaturated, substituted orunsubstituted, branched or unbranched, (hetero)aliphatic group having1-6 carbon atoms; and

R₂₁ is

or an aldehyde group.

In certain embodiments, X and Y can each be methylene; R₁ can be methyl;R₂, R₃ and the two carbon atoms directly bonded therewith can form a3,3-dimethyl cyclohexane ring;

R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₂, and R₁₃ can each be hydrogen; R₁₁ canbe an amide group, an acid group, an ester group, an aldehyde group, analcohol group, a carbamate group, a thiocarbamate, a carbonate, anitrile group, an amino group, or an imino group; and the bond betweenthe two carbon atoms directly bonded with R₁₀ and R₁₁ can be a doublebond.

In certain embodiments, X and Y can each be methylene; R₁ can be methyl;R₂, R₃ and the two carbon atoms directly bonded therewith can form a3,3-dimethyl cyclohexane ring; R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₂, and R₁₃can each be hydrogen; R₁₁ can be an amide group, an acid group, an estergroup, an aldehyde group, an alcohol group, a carbamate group, athiocarbamate, a carbonate, a nitrile group, an amino group, or an iminogroup; W can be —O—; R₁₂, R₁₃, R₁₄, and R₁₅ can each be hydrogen; G canbe ═O; and the bond between the two carbon atoms directly bonded withR₁₀ and R₁₁ can be a double bond.

In certain embodiments, a compound of Formula (II) can be of Formula(II-A):

In certain embodiments, a compound of Formula (II) can be of Formula(II-B):

In certain embodiments, a compound of Formula (II) can be of Formula(II-C):

In certain embodiments, a compound of Formula (II) can be of Formula(II-D):

In certain embodiments, G can be can be ═O. In certain embodiments, Gcan be —OR′ (e.g., —OH, —O(substituted or unsubstituted C₁₋₆ alkyl), or—OC(═O)(substituted or unsubstituted C₁₋₆ alkyl)). In certainembodiments, G can be can be ═S. In certain embodiments, G can be —SR′(e.g., —SH or —S(substituted or unsubstituted C₁₋₆ alkyl)). In certainembodiments, G can be —NHR′ (such as —NH(substituted or unsubstitutedC₁₋₆ alkyl) or —NHC(═O)(substituted or unsubstituted C₁₋₆ alkyl)) or—NH₂. In certain embodiments, W can be —O—. In certain embodiments, Wcan be —S—. In certain embodiments, W can be —NR′— (e.g., —N(substitutedor unsubstituted C₁₋₆ alkyl)- or —NH—). In certain embodiments, X can bemethylene. In certain embodiments, X can be ethanediyl, vinylene bridge,or propanediyl. In certain embodiments, Y can be methylene. In certainembodiments, Y can be ethanediyl, vinylene bridge, or propanediyl. Incertain embodiments, R₁ can be substituted or unsubstituted, branched orunbranched, C₁₋₆ alkyl (e.g., methyl, —CH₂OH, —CH₂C(═O)Me, or—CH₂C(═S)Me). In certain embodiments, R₁ cannot be —CH₃. In certainembodiments, R₂, R₃, and the two carbon atoms directly bonded therewithform cycloalkyl (e.g., a 3,3-dimethyl cyclohexane ring

that is unsubstituted or substituted (e.g., substituted with —OH)). Incertain embodiments, R₂, R₃, and the two carbon atoms directly bondedtherewith cannot form

that is unsubstituted. In certain embodiments, R₄, R₅, R₆, R₇, R₈, R₉,R₁₀, R₁₂, and R₁₃ can each be hydrogen. In certain embodiments, R₄ canbe hydrogen. In certain embodiments, R₄ can be substituted orunsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g., methyl or—CH₂OCF₃). In certain embodiments, R₄ cannot be hydrogen. In certainembodiments, R₅ can be hydrogen. In certain embodiments, R₅ can besubstituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g.,methyl). In certain embodiments, R₅ can be —OR′ (e.g., —OH). In certainembodiments, R₆ can be hydrogen. In certain embodiments, R₆ can besubstituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g.,methyl). In certain embodiments, at least one of R₅ and R₆ cannot behydrogen. In certain embodiments, R₇ can be hydrogen. In certainembodiments, R₇ can be substituted or unsubstituted, branched orunbranched, C₁₋₆ alkyl (e.g., methyl). In certain embodiments, R₈ can behydrogen. In certain embodiments, at least one of R₇ and R₈ cannot behydrogen. In certain embodiments, R₉ can be hydrogen. In certainembodiments, R₁₀ can be hydrogen. In certain embodiments, R₁₀ can be anamino group (e.g., —N(R′)₂, —NHR′, or —NH₂). In certain embodiments, R₁₁can be hydrogen. In certain embodiments, R₁₁ can be an amide group, anester group, an aldehyde group, a carbamate group, a thiocarbamate, anitrile group, an amino group, an imino group, or substituted orunsubstituted, branched or unbranched, C₁₋₆ alkyl. In certainembodiments, R₁₁ can be an ester group, an aldehyde group, a ketonegroup, or substituted or unsubstituted, branched or unbranched, C₁₋₆alkyl. In certain embodiments, R₁₁ can be substituted or unsubstituted,branched or unbranched, C₁₋₆ alkyl (e.g., —CH₂CF₃, —CH₂OR′ (such as—CH₂OH), —CH₂SR′ (such as —CH₂SH), —CH₂N(R′)₂ (such as —CH₂NHMe or—CH₂NH₂), or —CH₂C(═O)N(R′)₂ (such as —CH₂C(═O)NH(substituted orunsubstituted C₁₋₆ alkyl))). In certain embodiments, R₁₁ cannot be—CH₂OH. In certain embodiments, R₁₁ can be an ester group (e.g.,—C(═O)O(substituted or unsubstituted, branched or unbranched, C₁₋₆alkyl), such as —C(═O)OMe). In certain embodiments, R₁₁ can be analdehyde group. In certain embodiments, R₁₁ can be a ketone group (e.g.,—C(═O)-(substituted or unsubstituted, branched or unbranched, C₁₋₆alkyl), such as —C(═O)Me). In certain embodiments, R₁₂ can be hydrogen.In certain embodiments, R₁₃ can be hydrogen. In certain embodiments, R₁₄can be hydrogen. In certain embodiments, R₁₄ can be substituted orunsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g., —C(═O)OMe or—C(═O) (substituted or unsubstituted, C₂₋₂₀ alkenyl). In certainembodiments, R₂₁ can be

In certain embodiments, R₂₁ can be —CH₂OH. In certain embodiments, R₂₁can be an aldehyde group. In certain embodiments, R₁₅ can be hydrogen.In certain embodiments,

R₁₅ can be absent. In certain embodiments, the bond between the twocarbon atoms directly bonded with R₁₀ and R₁₁ can be a double bond. Incertain embodiments, the bond between the two carbon atoms directlybonded with R₁₀ and R₁₁ can be a single bond. In certain embodiments, R′can be hydrogen. In certain embodiments, R′ can be substituted orunsubstituted, branched or unbranched, C₁₋₆ alkyl (e.g., methyl, ethyl,propyl, or butyl).

In certain embodiments, at least one of R₄, R₅, R₆, R₇, R₈, R₉, and R₁₀cannot be hydrogen. In certain embodiments, R₁ cannot be —CH₃. Incertain embodiments, when R₂₁ is —CHO and G is —OH or ═O, R₁₁ cannot be—CHO.

In certain embodiments, the compound of Formula (II) cannot be of theformula:

wherein:

G is —OR′ or —NR′H;

R₁₁ is an amide group, a nitrile, an ester group, or substituted methyl;and

R₂₁ is an aldehyde group or —CH₂OR₁₄.

In certain embodiments, a compound described herein cannot be of theformula:

In certain embodiments, a compound described herein cannot be of theformula:

wherein R^(x) is a phosphorous-containing group.

Exemplary compounds described herein include, but are not limited to:

and pharmaceutically acceptable salts thereof, wherein

In still another aspect, this present disclosure features pharmaceuticalcompositions including one or more of the GLP-1 receptor modulatorsdescribed herein and a pharmaceutically acceptable carrier.

In yet another aspect, this present disclosure features methods forregulating blood glucose level and/or treating diabetes in a subject.The method comprises administering to a subject in need thereof aneffective amount of a pharmaceutical composition described herein. Incertain embodiments, the subject is a human (e.g., a human patienthaving, at risk for, or suspected of having diabetes, e.g., type I ortype II diabetes.

In still another aspect, this present disclosure features methods oftreating diabetes in a subject, the method including administering to asubject in need thereof an effective amount (e.g., a therapeuticallyeffective amount) of a pharmaceutical composition described herein.

The methods described above can also include the step of identifying asubject in need of the treatment, e.g., a human patient having or atrisk for developing abnormal blood glucose levels or any disorderassociated therewith.

In further another aspect, the present disclosure features kitscomprising a pharmaceutical composition described herein and optionally,instructions for using the kits.

Also within the scope of this present disclosure are a pharmaceuticalcomposition as described herein for use in regulating blood glucoselevel and/or treating diabetes in a subject, and the use of such apharmaceutical composition for the manufacture of a medicament forregulating blood glucose level and/or treating diabetes in a subject.

Other features or advantages of the present disclosure will be apparentfrom the following detailed description of several embodiments, and alsofrom the appending claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a chart showing the effect of GLP-1 (7-36) on endocytosismedicated by GLP-1 receptor. The GLP-1R/β-arrestin2 GFP double stableexpression U2OS cells were plated in 384-well plastic plates at adensity of 3000 cell/well and cultured overnight. Wells were treatedwith vehicle or various concentrations of GLP-1(7-36) for 60 min at roomtemperature in the presence (◯) or absence (□) of 1 μM of exendin 9.

FIG. 2 shows the activity of an ethanol extract of Hedychium coronarium(HC) in potentiating the GLP-1 activity. (Panel A) Cell images of GLP-1receptor endocytosis elicited by 0 or 4 nM of GLP-1 in the presence orabsence of 0.06 mg/ml ethanol extract of HC. (Panel B) Dose responsedata of GLP-1 from 0.15 nM to 324 nM on GLP-1 receptor activation in thepresence (▾) or absence (▪) of 0.0 6 mg/ml of ethanol extract of HC.(Panel C) Dose response data of ethanol extract of HC from 0.0025 mg/mlto 0.2 mg/ml on GLP-1 receptor activation by 4 nM of GLP-1.

FIG. 3 includes charts showing normal phase silica gel chromatograms ofHC ethyl acetate partition fraction. 7 g of EtOAc partition material wassubjected to normal phase silica gel chromatography and resolved into 37fractions. The activity was assayed for each fraction (the ability of0.002 mg/ml partially purified compounds to potentiate the receptorendocytosis elicited by 4 nM of GLP-1) and expressed as % of the maximalactivity elicited by 1 μM of GLP-1. ♦ represents weight of eachfraction. ▪ indicates the activity of each fraction. I is the pooledfraction 5 to fraction 12.

FIG. 4 shows an exemplary fractionation of I (the pooled fraction 5 tofraction 12) on a KROMASIL C₁₈ column. 1.7 gram of I was injected into aKROMASIL C₁₈ column (250×50 mm, 10 μm) eluted at flow rate of 109 ml/minwith a gradient started with 57% acetonitrile in water and finally with100% acetonitrile. Weight of each fraction (♦) and (▪) indicatesactivity of each fraction.

FIG. 5 shows exemplary results of a dose response analysis of galanal Bon GLP-1 (Panel A) or PTH (Panel B) induced receptor endocytosis. TheGLP-1R/3-arrestin2 GFP (Panel A) or PTHR/β-arrestin 2 GFP (Panel B)double stable expression U2OS cells were plated in 384-well plasticplates at a density of 3000 cell/well and cultured overnight. Dosetitration of galanal B on cell stimulated with 4 nM of GLP-1 7-36 (FIG.5A) or stimulated with 15 nM of PTH (Panel B). Panel C shows exemplaryresults of a dose response data of GLP-1 from 0.15 nM to 324 nM on GLP-1receptor activation in the presence (▾) or absence (▪) of 0.001 mg/ml ofgalanal B.

FIG. 6 shows that galanal B potentiated GLP-1 elicited GLP-1 receptorendocytosis. Dose response data of GLP-1 from 0.15 nM to 324 nM on GLP-1receptor activation in the presence (▾) of 0.001 mg/ml of galanal B(Panel A) or in the absence (▪) of 0.001 mg/ml of galanal B (Panel B).

FIG. 7 shows that galanal B, compound 1, and compound 2 increased thepotency of GLP-1 dependent receptor endocytosis. Dose response titrationof GLP-1 from 0.15 nM to 324 nM on GLP-1 receptor endocytosis in thepresence (◯), (∇), (□) of 0.0001 mg/ml of galanal B, 0.001 mg/ml ofcompound 1, 0.001 mg/ml of compound 2, respectively, or GLP-1 alone (▴).

FIG. 8 shows that exendin 9 diminished positive modulation effectcompound 1, compound 2, and galanal B on GLP-1 elicited GLP-1 receptorendocytosis. (Panel A) Titration of GLP-1 on GLP-1 receptor endocytosisin the presence of 0.0001 mg/ml of galanal B (), absence of galanal B(▴), and in the presence of 0.0001 mg/ml of galanal B plus 1.8 mM ofExendin 9 (▪). (Panel B) Titration of GLP-1 on GLP-1 receptorendocytosis in the presence of 0.001 mg/ml of compound 2 (), absence ofcompound 2 (▴) and in the presence of 0.001 mg/ml of compound 2 plus 1.8mM of Exendin 9 (▪). (Panel C) Titration of GLP-1 on GLP-1 receptorendocytosis in the presence of 0.001 mg/ml of compound 1 (), absence ofcompound 1 (▴) and in the presence of 0.001 mg/ml of compound 1 and 1.8mM of Exendin 9 (▪).

FIG. 9 shows that compound 1 suppressed, and compound 2 potentiated,GLP-1 dependent cAMP production in RINm5F cells (Panel A) Dose responsetitration of GLP-1 in the presence of 0.003 mg/ml of galanal B (◯),compound 2 (⋄), compound 1 (∇), or GLP-1 alone (). (Panel B) Doseresponse of galanal (◯) or compound 2 (Δ) on cAMP production in RINm5Fcells stimulated by 3 nM of GLP-1. (Panel C) Dose response of compound 1() on cAMP production in RINm5F cells elicited by 60 nM of GLP-1.

FIG. 10 shows that potentiation effect of compound 2 on GLP-1 elicitedcAMP generation is blocked by exendin 9 and MDL 12330A. (Panel A)Titration of exendin 9 on cAMP production in RINm5F cells stimulated by2 nM of GLP-1 in the presence (Δ) and absence () of 0.0025 mg/ml ofcompound 2. (Panel B) Titration of GLP-1 on cAMP production in RIMm5Fcells (◯) or in the presence of 0.0025 mg/ml of compound 2 (a) or in thepresence of 0.0025 mg/ml of compound 2 plus 250 mM of MDL 12330A (b).

FIG. 11 shows the effect of compound 1 and compound 2 on cAMP productionin RINm5F cells elicited by GIP and Glucagon. (Panel A) Titration of GIPon the production of cAMP from RINm5F cells (Δ) or in the presence of0.025 mg/ml of compound 2 (□) or compound 1 (◯). (Panel B) Titration ofglucagon on the production of cAMP from RINm5F cells (▴) or in thepresence of 0.025 mg/ml of compound 2 (▪) or compound 1 ().

DETAILED DESCRIPTION

In an attempt to identify orally active and physiologically morecompliant GLP-1 therapeutics for diabetes (e.g., type II diabetes) andcompounds that selectively regulates the GLP-1 pathway, edible plantswere screened for activities that modulate the GLP-1 receptor signaling.In particular, plant extracts were screened to identify components thatpositively modulate GLP-1 receptor signaling in a GLP-1 dependentmanner. The compounds identified in the screening process do not actmerely in an on-and-off manner, as those GLP-1 therapies known in theart. Rather, the positive modulators identified from plants act morelike a dimmer switch, providing control over the intensity of activationaccording to the secreting level of endogenous GLP-1 and allowing thebody to retain its physiological control over initiating receptoractivation.

Accordingly, described herein are novel GLP-1 receptor modulators (e.g.,activators) such as compounds having Formula (I) or Formula (II) asdescribed herein, or pharmaceutically acceptable salts thereof, and usesthereof in regulating blood glucose levels and treating diabetes such astype I or type II diabetes. The GLP-1 receptor modulators describedherein activates GLP-1 receptor only in the presence of GLP-1, which isdifferent from the GLP-1 independent GLP-1 receptor activators known inthe art. See, e.g., U.S. Pat. No. 8,501,982.

Preparation of GLP-1 Receptor Modulators

The compounds described herein can be prepared by methods well known inthe art. In some examples, the compounds can be isolated from a nativesource, such as a plant. In other examples, the compounds are chemicallysynthesized following routine synthetic routes, e.g., by Scheme 1 andScheme 2 shown below.

The chemicals used in the above-described synthetic routes may include,for example, solvents, reagents, catalysts, and protecting group anddeprotecting group reagents. The methods described above may alsoadditionally include steps, either before or after the steps describedspecifically herein, to add or remove suitable protecting groups inorder to ultimately allow synthesis of the compounds described herein.In addition, various synthetic steps may be performed in an alternatesequence or order to give the desired compounds. Synthetic chemistrytransformations and protecting group methodologies (protection anddeprotection) useful in synthesizing applicable compounds describedherein are known in the art and include, for example, those described inR. Larock, Comprehensive Organic Transformations, VCH Publishers (1989);T. W. Greene and P. G. M. Wuts, Protective Groups in Organic Synthesis,3rd Ed., John Wiley and Sons (1999); L. Fieser and M. Fieser, Fieser andFieser's Reagents for Organic Synthesis, John Wiley and Sons (1994); andL. Paquette, ed., Encyclopedia of Reagents for Organic Synthesis, JohnWiley and Sons (1995) and subsequent editions thereof.

A compound thus obtained can be further purified by methods known in theart (e.g., flash column chromatography, high performance liquidchromatography, or crystallization). The bioactivity of any of thecompounds described herein can be verified via in vitro or in vivo assaysystems known in the art, e.g., those described in the Examples below.

Pharmaceutical Compositions Comprising GLP-1 Receptor Modulators andTherapeutic Uses Thereof

Any of the compounds described herein may be useful in regulating bloodglucose levels or treating diabetes in a subject via, e.g., modulatingthe GLP-1 receptor signaling pathways.

A pharmaceutical composition that includes one or more compounddescribed herein and a pharmaceutically acceptable carrier. In certainembodiments, a pharmaceutical composition described herein includes acompound described herein in an amount sufficient to regulate bloodglucose level in a subject. The carrier in the pharmaceuticalcomposition must be “acceptable” in the sense that it is compatible withthe active ingredient of the composition, and preferably, capable ofstabilizing the active ingredient and not deleterious to the subject tobe treated. For example, solubilizing agents such as cyclodextrins,which form specific, more soluble complexes with the compounds describedherein, or one or more solubilizing agents, can be utilized aspharmaceutical excipients for delivery of the compounds describedherein. Examples of other carriers include colloidal silicon dioxide,magnesium stearate, cellulose, sodium lauryl sulfate, and D&C Yellow#10.

To practice the methods described herein, an effective amount of apharmaceutical composition as described herein can be administered to asubject in need of the treatment via a suitable route.

An “effective amount” is that amount of the one or more GLP-1 receptormodulator that alone, or together with further doses, produces thedesired response, e.g. reduce the blood glucose levels in the subject.In the case of treating a particular disease or condition such as Type Ior Type II diabetes, characterized by dysregulated GLP-1 receptorsignaling, the desired response is inhibiting the progression of thedisease or condition. This may involve only slowing the progression ofthe disease temporarily, although more preferably, it involves haltingthe progression of the disease permanently. This can be monitored byroutine methods or can be monitored according to routine medicalpractices. The desired response to treatment of the disease or conditionalso can be delaying the onset or even preventing the onset of thedisease or condition.

Effective amounts will depend, of course, on the particular conditionbeing treated, the severity of the condition, the individual patientparameters including age, physical condition, size, gender and weight,the duration of the treatment, the nature of concurrent therapy (ifany), the specific route of administration and like factors within theknowledge and expertise of the health practitioner. These factors arewell known to those of ordinary skill in the art and can be addressedwith no more than routine experimentation. It is generally preferredthat a maximum dose of the individual components or combinations thereofbe used, that is, the highest safe dose according to sound medicaljudgment. It will be understood by those of ordinary skill in the art,however, that a patient may insist upon a lower dose or tolerable dosefor medical reasons, psychological reasons or for virtually any otherreasons.

The subject to be treated by any of the methods described herein can bea human patient, e.g., a human patient having, at risk for, or suspectedof having an elevated blood glucose level or any disease/conditionassociated therewith, such as Type I or Type II diabetes, gestationaldiabetes, obesity, excessive appetite, insufficient satiety, and ametabolic disorder. Such a human patient can be identified by routinemedical practices. Alternatively, the subject can be a non-human mammal,e.g., dog, cat, cow, pig, horse, sheep, or goat.

The GLP-1 receptor modulator activates GLP-1 receptor only in thepresence of GLP-1. Thus, when a subject's endogenous level of GLP-1 istoo low, any of the moculators described herein can be co-administeredwith GLP-1 or a functional variant thereof.

The terms “treatment,” “treat,” and “treating” refer to reversing,alleviating, delaying the onset of, or inhibiting the progress ofdiabetes. In some embodiments, treatment may be administered after oneor more signs or symptoms have developed or have been observed. In otherembodiments, treatment may be administered in the absence of signs orsymptoms of diabetes. For example, treatment may be administered to asusceptible individual prior to the onset of symptoms (e.g., in light ofa history of symptoms and/or in light of genetic or other susceptibilityfactors). Treatment may also be continued after symptoms have resolved,for example, to delay or prevent recurrence.

The pharmaceutical composition described herein can be administeredorally, parenterally, by inhalation spray, topically, rectally, nasally,buccally, vaginally or via an implanted reservoir. The term “parenteral”as used herein includes subcutaneous, intracutaneous, intravenous,intramuscular, intraarticular, intraarterial, intrasynovial,intrasternal, intrathecal, intralesional and intracranial injection orinfusion techniques.

A sterile injectable composition, e.g., a sterile injectable aqueous oroleaginous suspension, can be formulated according to techniques knownin the art using suitable dispersing or wetting agents (such as TWEEN80) and suspending agents. The sterile injectable preparation can alsobe a sterile injectable solution or suspension in a non-toxicparenterally acceptable diluent or solvent, for example, as a solutionin 1,3-butanediol. Among the acceptable vehicles and solvents that canbe employed are mannitol, water, Ringer's solution and isotonic sodiumchloride solution. In addition, sterile, fixed oils are conventionallyemployed as a solvent or suspending medium (e.g., synthetic mono- ordi-glycerides). Fatty acids, such as oleic acid and its glyceridederivatives are useful in the preparation of injectables, as are naturalpharmaceutically-acceptable oils, such as olive oil or castor oil,especially in their polyoxyethylated versions. These oil solutions orsuspensions can also contain a long-chain alcohol diluent or dispersant,or carboxymethyl cellulose or similar dispersing agents. Other commonlyused surfactants such as Tweens or Spans or other similar emulsifyingagents or bioavailability enhancers which are commonly used in themanufacture of pharmaceutically acceptable solid, liquid, or otherdosage forms can also be used for the purposes of formulation.

A pharmaceutical composition for oral administration can be any orallyacceptable dosage form including, but not limited to, capsules, tablets,emulsions and aqueous suspensions, dispersions and solutions. In thecase of tablets for oral use, carriers which are commonly used includelactose and corn starch. Lubricating agents, such as magnesium stearate,are also typically added. For oral administration in a capsule form,useful diluents include lactose and dried corn starch. When aqueoussuspensions or emulsions are administered orally, the active ingredientcan be suspended or dissolved in an oily phase combined with emulsifyingor suspending agents. If desired, certain sweetening, flavoring, orcoloring agents can be added. A nasal aerosol or inhalation compositioncan be prepared according to techniques well-known in the art ofpharmaceutical formulation and can be prepared as solutions in saline,employing benzyl alcohol or other suitable preservatives, absorptionpromoters to enhance bioavailability, fluorocarbons, and/or othersolubilizing or dispersing agents known in the art. A pharmaceuticalcomposition described herein can also be administered in the form ofsuppositories for rectal administration.

Also within the scope of the present disclosure are kits (e.g.,pharmaceutical packs) comprising one or more compound or pharmaceuticalcompositions described herein. Such a kit can further comprise acontainer (e.g., a vial, ampule, bottle, syringe, and/or dispenserpackage, or other suitable container) for placing thecompounds/compositions. In some embodiments, a kit described herein mayinclude a second container comprising a pharmaceutically acceptableexcipient for dilution or suspension of a compound or pharmaceuticalcomposition described herein. In some embodiments, the compound orpharmaceutical composition provided in the first container and thesecond container are combined to form one unit dosage form.

A kit described herein may include instructions for using the kit (e.g.,for administering a compound or pharmaceutical composition containedtherein to a subject). A kit described herein may also includeinformation as required by a regulatory agency such as the FDA. Incertain embodiments, the information included in the kit is prescribinginformation. A kit described herein may include one or more additionalpharmaceutical agents described herein as a separate composition.

A compound or pharmaceutical composition described herein may beadministered concurrently with, prior to, or subsequent to one or moreadditional pharmaceutical agents, which may be useful as, e.g.,combination therapies. The additional pharmaceutical agents may betherapeutically active agents or prophylactically active agents.

EXAMPLES

Without intent to limit the scope of the present disclosure, exemplarycompounds and methods of using or making such, as well as their relatedresults according to the embodiments of the present disclosure are givenbelow. Note that titles or subtitles may be used in the examples forconvenience of a reader, which in no way should limit the scope of thepresent disclosure. Moreover, certain theories are proposed anddisclosed herein; however, in no way they, should limit the scope of thepresent disclosure so long as the present disclosure is practicedaccording to the present disclosure without regard for any particulartheory or scheme of action.

Example 1 Synthesis of Exemplary GLP-1 Receptor Modulators (1)(±)-(4aS,6aR,11aS,11bR)-7-hydroxy-4,4,11b-trimethyltetradecahydro-1H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-002)

A solution of(±)-(4aS,6aR,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyltetradecahydro-1H-cyclohepta[a]naphthalen-7-ol, TEMPO, and TBACl in DCMand aqueous solution of NaHCO₃ (0.5M) and K₂CO₃ (0.05M) were vigorouslystirred at room temperature. NCS was then added. Stirring was maintainedand the reaction monitored by TLC. The reaction was quenched with sat.NH₄Cl, the organic layer was separated, and the aqueous layer wasextracted with DCM (three times). The DCM extracts were washed withbrine, dried over Na₂SO₄, and concentrated in vacuo. The residue wascoated on silica gel and purified by flash column chromatography to give(±)-(4aS,6aR,11aS,11bR)-7-hydroxy-4,4,11b-trimethyltetradecahydro-1H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-002) as a white solid.

(2) (±)-(6aS,11aS,11bR)-methyl4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-01)

A solution of (±)-(6aS,11aS,11bR)-methy 4,4,11b-trimethyl-7-oxo2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-012) (757 mg, 2.38 mmol) and DBU (0.71 mL, 4.75 mmol) in benzene(48.0 mL) was refluxed for 5 h. The volatiles were removed in vacuo andthe residue was purified by flash chromatography (EtOAc:hexanes, 1:19)to afford (±)-(6aS,11aS,11bR)-methyl4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-011) (691 mg, 91%) as a white solid. Data for RJ-011: Mp 93-94° C.;IR (film) 2944, 2867, 2845, 1711, 1643, 1436, 1388, 1366, 1259, 1199,1161, 1122, 1088, 1059 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 7.13-7.10 (m,1H), 3.74 (s, 3H), 3.51-3.41 (m, 2H), 2.63 (td, J=12.0 Hz, J=3.6 Hz,1H), 2.46-2.37 (m, 1H), 2.16-2.12 (m, 1H), 1.82-1.67 (m, 3H), 1.65-1.52(m, 2H), 1.52-1.36 (m, 3H), 1.36-1.23 (m, 1H), 1.15 (td, J=13.4 Hz,J=4.0 Hz, 1H), 0.95-0.88 (m, 2H), 0.85 (s, 6H), 0.81 (s, 3H); ¹³C NMR(125 MHz, CDCl₃) δ 211.0, 166.9, 162.7, 126.8, 54.6, 52.6, 52.2, 52.1,41.8, 40.2, 38.4, 37.5, 33.3, 33.2, 29.0, 27.1, 21.4, 20.9, 18.6, 14.3;HRMS (APCI) calcd for C₂₀H₃₀O₃ [M+Na]⁺: 341.2093. found: 341.2092.

(3) (±)-(6aS,11aS,11bR)-methy4,4,11b-trimethyl-7-oxo2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-012)

To a solution of (±)-(6aS,11aS,11bR)-methyl 4,4,11b-trimethyl-7-oxotetradecahydro-1H-cyclo-hepta-[a]naphthalene-9-carboxylate (RJ-015) (872mg, 2.72 mmol) and NEt₃ (1.5 mL, 10.89 mmol) in CH₂Cl₂ (27.0 mL) wasadded TMSOTf (1.0 mL, 5.4 mmol) at 0° C., and stirring was continued for2 h. The reaction contents were quenched with sat. NaHCO_(3(aq)) (60 mL)at 0° C., and the aqueous layer was extracted with CH₂Cl₂ (3×30 mL). Theorganic extracts were combined, washed with brine (60 mL), dried withNa₂SO₄, and concentrated by rotary evaporator. To a solution of thedried residue in THF (27.0 mL) was added PhSeCl (626 mg, 3.27 mmol) at−78° C. The mixture was stirred at −78° C. for 30 min before theaddition of pyridine (0.44 mL, 5.45 mmol) and 30% H₂O₂ (0.48 mL, 5.45mmol). The mixture was allowed to warm to 0° C. and stirred for 1 h. Thereaction was quenched by sat. NaHCO_(3(aq)) (60 mL), and the aqueouslayer was extracted with ether (3×30 mL). The organic extracts werecombined, washed with brine (60 mL), dried over Na₂SO₄, and concentratedin vacuo. The residue was purified by flash chromatography(EtOAc:hexanes, 4:96) to afford (±)-(6aS,11aS,11bR)-methy4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-012) (815 mg, 95%) as a colorless oil. Data for RJ-012: IR (film)2925, 2866, 1722, 1667, 1436, 1388, 1366, 1228, 1135, 1022 cm⁻¹; ¹H NMR(400 MHz, CDCl₃) δ 6.85 (s, 1H), 3.77 (s, 3H), 2.71-2.57 (m, 3H),1.91-1.78 (m, 3H), 1.73-1.63 (m, 1H), 1.63-1.52 (m, 1H), 1.50-1.28 (m,5H), 1.28-1.21 (m, 1H), 1.14 (td, J=13.0 Hz, J=4.0 Hz, 1H), 0.96-0.86(m, 2H), 0.86 (s, 3H), 0.84 (s, 3H), 0.81 (s, 3H); ¹³C NMR (125 MHz,CDCl₃) δ 208.0, 167.9, 143.2, 135.6, 55.0, 54.8, 52.4, 51.2, 42.0, 38.2,37.7, 33.3, 33.2, 31.4, 30.8, 25.7, 21.5, 21.4, 18.5, 13.9; HRMS (ESI)calcd for C₂₀H₃₀O₃ [M+H]⁺: 319.2273. found: 319.2270.

(4)(±)-(6aS,7R,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalen-7-ol(RJ-013) &(±)-(6aS,7S,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalen-7-ol(RJ-014)

To a solution of (±)-(6aS,1aS,11bR)-methyl4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-011) (600 mg, 1.88 mmol) in DCM (19 mL) at −78° C. was added DIBALsolution (1.0 M in toluene, 7.5 mL, 7.54 mmol), and the stirring wascontinued for 3 h. The reaction was quenched by 1N HCl_((aq)) (40 mL)and allowed to warm to room temperature. The phases were separated, andthe aqueous layer was extracted with DCM (3×20 mL). The organic extractswere combined, washed with brine (40 mL), dried over Na₂SO₄, andconcentrated in vacuo. The residue was purified by flash chromatography(gradient from 1:9→1:4-2:3 EtOAc:hexanes) to afford(±)-(6aS,7R,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalen-7-ol(RJ-013) (296 mg, 54%) and(±)-(6aS,7S,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalen-7-ol(RJ-014) (200 mg, 36%). Both RJ-013 and RJ-014 are white solids. Datafor RJ-013: Mp 134-135° C.; IR (film): 3350, 2918, 2865, 2840, 1652,1452, 1384, 1123, 1088, 1035, 999 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ5.88-5.84 (m, 1H), 3.99 (s. 2H), 3.38-3.33 (m, 1H), 2.53 (dd, J=15.0 Hz,J=8.4 Hz, 1H), 2.38-2.30 (m, 1H), 2.20 (dd, J=15.0 Hz, J=8.4 Hz, 1H),2.09-2.01 (m, 1H), 1.95-1.80 (m, 2H), 1.72-1.60 (m, 4H), 1.60-1.50 (m,1H), 1.49-1.41 (m, 1H), 1.41-1.34 (m, 1H), 1.34-1.24 (m, 1H), 1.12 (td,J=13.0 Hz, J=4.0 Hz, 1H), 1.05-0.91 (m, 2H), 0.90-0.77 (m, 2H), 0.84 (s,3H), 0.82 (s, 3H), 0.81 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ 136.6,128.8, 75.0, 68.1, 54.8, 53.5, 48.5, 42.0, 38.8, 37.8, 34.9, 33.4, 33.3,32.7, 26.3, 21.7, 21.6, 18.9, 14.0; HRMS (MALDI) calcd for C₁₉H₃₂O₂[M+Na]⁺: 315.2300. found: 315.2314. Data for RJ-014: Mp 89-91° C.; IR(film): 3354, 2921, 2865, 1449, 1386, 1365, 1062, 1045, 1000, 738 cm⁻¹;¹H NMR (500 MHz, CDCl₃) δ 5.89 (t, J=7.3 Hz, 1H), 3.95-3.89 (m, 2H),3.71 (d, J=5.7 Hz, 1H), 2.60-2.54 (m, 1H), 2.44 (dd, J=14.5 Hz, J=7.0Hz, 1H), 2.16 (dd, J=14.0 Hz, J=8.5 Hz, 1H), 1.90-1.83 (m, 1H),1.80-1.71 (m, 1H), 1.67-1.56 (m, 3H), 1.56-1.46 (m, 2H), 1.46-1.39 (m,1H), 1.39-1.26 (m, 1H), 1.16-1.08 (m, 1H), 0.95 (t, J=10.8 Hz, 1H),0.91-0.77 (m, 2H), 0.84 (s, 3H), 0.81 (s, 3H), 0.81 (s, 3H), 0.80-0.77(m, 1H); ¹³C NMR (100 MHz, CDCl₃) δ 137.5, 130.1, 70.0, 67.8, 54.5,47.3, 47.3, 42.0, 39.2, 37.5, 35.4, 33.5, 33.4, 32.1, 27.4, 22.0, 21.5,18.9, 13.9; HRMS (ESI) calcd for C₁₉H₃₂O₂ [M+Na]⁺: 315.2300. found:315.2294.

(5) (±)-(6aS,11aS,11bR)-methyl4,4,11b-trimethyl-7-oxotetradecahydro-1H-cyclo-hepta-[a]naphthalene-9-carboxylate(RJ-015)

To a solution of(±)-(4aS,4bR,10aS)-4b,8,8-trimethyldodecahydro-phenanthren-1(4bH)-one(890 mg, 3.59 mmol) in THF (18 mL) was added LHMDS (1.0 M in THF, 5.4mL, 5.38 mmol) at −78° C. The mixture was allowed to warm slowly to 0°C. over the course of 2 h. Then, cooled down to −78° C., and NCCOOMe(0.43 mL, 5.38 mmol) and TMEDA (0.73 mL, 5.38 mmol) were added dropwiseto the reaction mixture. Let it slowly warmed to room temperature andthe stirring was continued overnight. The reaction contents werequenched with 1N HCl_((aq)) (40 mL) and extracted with DCM (3×20 mL).The organic extracts were combined, washed with brine (30 mL), driedover Na₂SO₄, and concentrated in vacuo. To a solution of Et₂Zn (1.0 M inhexane, 5.4 mL, 5.38 mmol) in DCM (30 mL) under ice-bath was added neatCH₂I₂. The mixture was stirred at 0° C. for 1 h, and then theaforementioned crude in DCM (30 mL) was added. After 5 minutes, removedthe ice-bath, and the stirring was continued for 3 h at roomtemperature. The reaction contents were quenched with sat. NH₄Cl_((aq))at 0° C. and allowed to warm to room temperature. The phases wereseparated, and the aqueous layer was extracted with DCM (3×30 mL). Theorganic extracts were combined, washed with sat. NaHCO_(3(aq)) (80 mL)and brine (80 mL), dried over Na₂SO₄, and concentrated in vacuo. Theresidue was purified by flash column chromatography (gradient from1:48→1:24 EtOAc:hexanes) to afford (±)-(6aS,11aS,11bR)-methyl4,4,11b-trimethyl-7-oxotetradecahydro-1H-cyclo-hepta-[a]naphthalene-9-carboxylate(RJ-015) (918 mg, 80%) as a white solid. Data for RJ-015: Mp 67-68° C.;IR (film) 2924, 2852, 1739, 1707, 1461, 1365, 1277, 1199, 1174 cm⁻¹; ¹HNMR (400 MHz, CDCl₃) δ 3.67 (s. 3H), 2.85-2.70 (m, 3H), 2.47 (td, J=12.0Hz, J=4.0 Hz, 1H), 2.18-2.08 (m, 1H), 1.82-1.71 (m, 3H), 1.70-1.63 (m,1H), 1.60-1.21 (m, 7H), 1.13 (td, J=13.0 Hz, J=4.0 Hz, 1H), 1.04-0.96(m, 1H), 0.93-0.85 (m, 2H), 0.84 (s, 3H), 0.81 (s, 3H), 0.79 (s, 3H);¹³C NMR (100 MHz, CDCl₃) δ 213.9, 174.8, 54.9, 53.9, 53.5, 51.8, 42.1,42.0, 39.5, 38.6, 37.9, 33.4, 33.3, 29.6, 29.6, 23.8, 21.6, 21.0, 18.8,14.0; HRMS (EI) calcd for C₂₀H₃₂O₃ [M]⁺: 320.2351. found: 320.2352.

(6)(±)-(6aS,11aS,11bR)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-017)

To a solution of(±)-(6aS,7S,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalen-7-ol(RJ-014) (6.8 mg, 0.023 mmol) in DCM (0.27 mL) at room temperature wasadded Dess-Martin periodinane (29.3 mg, 0.069 mmol), and the stirringwas continued for 6 h. The reaction was quenched by 1M Na₂SO_(3(aq))(0.5 mL) and sat. NaHCO_(3(aq)) (0.5 mL) and stirred for another 30minutes. The phases were separated, and the aqueous layer was extractedwith DCM (3×4 mL). The organic extracts were combined, washed with brine(10 mL), dried over Na₂SO₄, and concentrated in vacuo. The residue waspurified by flash chromatography (1:19 EtOAc:hexanes) to afford(±)-(6aS,11aS,11bR)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-017) (4.4 mg, 65%). Data for RJ-017: Mp 87-88° C.; IR (film): 2927,2867, 2837, 1707, 1686, 1639, 1461, 1444, 1388, 1366, 1251, 1152, 1139,1114 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 9.39 (s, 1H), 6.85-6.82 (m, 1H),3.45-3.35 (m, 2H), 2.72-2.62 (m, 1H), 2.56 (td, J=12.0 Hz, J=4.0 Hz,1H), 2.24-2.13 (m, 1H), 1.88-1.79 (m, 2H), 1.79-1.72 (m, 1H), 1.71-1.66(m, 1H), 1.66-1.58 (m, 1H), 1.54-1.30 (m, 4H), 1.18 (td, J=13.4 Hz,J=4.0 Hz, 1H), 1.00-0.90 (m, 2H), 0.88 (s, 6H), 0.84 (s, 3H); ¹³C NMR(100 MHz, CDCl₃) δ 210.6, 192.3, 153.8, 137.3, 54.7, 53.9, 51.0, 41.8,38.6, 37.4, 36.4, 33.3, 33.3, 29.8, 28.6, 21.5, 21.0, 18.7, 14.2; HRMS(EI) calcd for C₁₉H₂₈O₂ [M]⁺: 288.2089. found: 288.2084.

(7)(±)-(7S,11bR)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-018)

A solution of(±)-(6aS,7S,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalen-7-ol(RJ-014) (58 mg, 0.20 mmol), TEMPO (3.1 mg, 0.02 mmol), and TBACl (5.5mg, 0.02 mmol) in DCM (2 mL) and aqueous solution of NaHCO₃ (0.5M, 1 mL)and K₂CO₃ (0.05M, 1 mL) were vigorously stirred at room temperature. NCS(53 mg, 0.40 mmol) was then added. Stirring was maintained and thereaction monitored by TLC. After 8 h, the reaction was quenched withsat. NH₄Cl (4 mL), the organic layer was separated, and the aqueouslayer was extracted with DCM (3×5 mL). The DCM extracts were washed withbrine (15 mL), dried over Na₂SO₄, and concentrated in vacuo. The residuewas coated on silica gel and purified by flash column chromatography(gradient from 1:19→1:4 EtOAc:hexanes) to give(±)-(7S,11bR)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-018) (43 mg, 75%) as a white solid. Data for RJ-018: Mp 148-150° C.;IR (film) 3470, 2934, 2918, 2859, 2846, 1671, 1645, 1444, 1387, 1109,1082, 1046, 737 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 9.39 (s, 1H), 6.96-6.92(m, 1H), 3.82 (d, J=6.8 Hz, 1H), 2.97 (dd, J=15.2 Hz, J=8.0 Hz, 1H),2.53 (dd, J=14.6 Hz, J=9.0 Hz, 1H), 2.30 (d, J=15.6 Hz, 1H), 2.11-2.00(m, 1H), 1.90-1.59 (m, 6H), 1.59-1.49 (m, 1H), 1.49-1.34 (m, 3H),1.34-1.21 (m, 1H), 1.18-1.07 (m, 2H), 0.90 (dd, J=12.9 Hz, J=3.5 Hz,1H), 0.85 (s, 3H), 0.84 (s, 3H), 0.81 (s, 3H); ¹³C NMR (125 MHz, CDCl₃)δ 193.8, 156.3, 142.3, 69.8, 54.6, 47.2, 46.1, 41.8, 39.1, 37.7, 33.4,33.4, 30.8, 29.2, 28.8, 21.8, 21.4, 18.8, 14.0; HRMS (ESI) calcd forC₁₉H₃₀O₂ [M+Na]⁺: 313.2143. found: 313.2151.

(8)(±)-(7R,11bR)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-019)

A solution of(±)-(6aS,7R,11aS,11bR)-9-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalen-7-ol(RJ-013) (30 mg, 0.10 mmol), TEMPO (1.6 mg, 0.01 mmol), and TBACl (2.8mg, 0.01 mmol) in DCM (1 mL) and aqueous solution of NaHCO₃ (0.5M, 0.5mL) and K₂CO₃ (0.05M, 0.5 mL) were vigorously stirred at roomtemperature. NCS (27.5 mg, 0.21 mmol) was then added. Stirring wasmaintained and the reaction monitored by TLC. After 24 h, the reactionwas quenched with sat. NH₄Cl (4 mL), the organic layer was separated,and the aqueous layer was extracted with DCM (3×5 mL). The DCM extractswere washed with brine (15 mL), dried over Na₂SO₄, and concentrated invacuo. The residue was coated on silica gel and purified by flash columnchromatography (gradient from 1:9→1:4 EtOAc:hexanes) to give(±)-(7R,11bR)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-019) (19 mg, 64%) as a white solid. Data for RJ-019: Mp 142-144° C.;IR (film): 3507, 2963, 2917, 2863, 2844, 1678, 1648, 1436, 1384, 1345,1302, 1212, 1041, 1007 cm⁻¹; ¹H NMR (500 MHz, CDCl₃) δ 9.38 (s, 1H),6.96-6.93 (m, 1H), 3.49-3.43 (m, 1H), 2.70 (dd, J=16.0 Hz, J=8.5 Hz,1H), 2.63-2.49 (m, 2H), 2.30-2.20 (m, 1H), 2.07-2.00 (m, 1H), 1.89-1.82(m, 1H), 1.79-1.70 (m, 1H), 1.70-1.52 (m, 4H), 1.52-1.43 (m, 1H),1.43-1.29 (m, 2H), 1.14 (td, J=13.5 Hz, J=3.0 Hz, 1H), 1.09-0.93 (m,2H), 0.87 (s, 3H), 0.85 (s, 3H), 0.82 (s, 3H), 0.82-0.78 (m, 1H); ¹³CNMR (125 MHz, CDCl₃) δ 193.9, 157.6, 140.5, 74.4, 54.8, 53.1, 48.1,42.0, 38.8, 38.0, 33.4, 33.4, 32.6, 28.8, 28.1, 21.7, 21.6, 18.9, 14.0;HRMS (ESI) calcd for C₁₉H₃₀O₂ [M+Na]⁺: 313.2143. found: 313.2137.

(9)(6aR,1aR,11bS)-methyl6a-(hydroxymethyl)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-022)

A mixture of Cp₂TiCl₂ (794 mg, 2.20 equiv.) and Zinc powder (625 mg,6.60 equiv) in deoxygenated THF (14 mL) was stirred at room temperature(30 min) until the red solution turned green. The green Ti(III) solutionwas slowly added via cannula to the stirred solution of (E)-methyl2-(cyanomethyl)-4-((1R,2R,8aS)-5,5,8a-trimethyloctahydro-1H-spiro[naphthalene-2,2′-oxiran]-1-yl)but-2-enoate (500 mg,1.45 mmol) in THF (15 mL) and stirred for 12 h. After this, an excess ofsaturated NaH₂PO₄ was added, and the mixture was stirred for 30 min. Themixture was filtered to remove insoluble titanium salts. The product wasextracted into ether (3×30 mL), and the combined organic layers werewashed with saturated NaHCO₃ (20 mL) and brine, dried over Na₂SO₄,concentrated and the crude product was column chromatographied(EtOAc-hexanes, 1:9) to afford(6aR,1aR,11bS)-methyl6a-(hydroxymethyl)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-022) as colorless needles (302 mg, 60%).

Characteristic data of RJ-022: [α]²⁵ _(D) −21.1 (c 0.93, CHCl₃); mp179-180° C. ¹H NMR (400 MHz, CDCl₃) δ 7.07 (dt, J=6.2, 3.1 Hz, 1H),4.14-3.98 (m, 2H), 3.93 (ddd, J=13.9, 6.7, 2.8 Hz, 1H), 3.74 (s, 3H),3.49 (d, J=13.9 Hz, 1H), 2.80 (dd, J=8.0, 5.8 Hz, 1H), 2.65-2.44 (m,2H), 2.18 (dd, J=11.8, 2.1 Hz, 1H), 2.02-1.95 (m, 1H), 1.81 (d, J=12.4Hz, 1H), 1.66 (ddd, J=14.0, 8.7, 3.8 Hz, 2H), 1.53-1.34 (m, 5H), 1.18(td, J=13.5, 4.1 Hz, 2H), 0.95 (s, 3H), 0.88 (s, 3H), 0.82 (s, 3H). ¹³CNMR (100 MHz, CDCl₃) δ 214.6, 167.0, 143.7, 124.3, 63.3, 56.8, 56.5,52.2, 50.6, 41.6, 39.8, 37.9, 37.7, 33.4, 33.1, 32.4, 26.3, 21.3, 18.4,18.1, 16.1. IR (film) 3542, 2935, 1708, 1702, 1640, 1440, 1386, 1263,1165, 1115, 1060, 753 cm⁻¹. HRMS (FAB+) calcd for C₂₁H₃₃O₄ [(M+H)⁺]349.2379. found 349.2380.

(12)(7S,11aS,11bR)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylicacid (RJ-026)

A solution of sodium chlorite (12 mg, 0.13 mmol) and NaH₂PO₄ (41 mg,0.34 mmol) in H₂O (0.2 mL) was added dropwise to a rapidly stirredsolution of(±)-(7S,11bR)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carbaldehyde(RJ-018) (10 mg, 0.034 mmol) and 2-methyl-2-butene (36 μL, 0.34 mmol) intert-butyl alcohol (0.34 mL) at room temperature and the stirring wascontinued for 30 h. The reaction mixture was made basic with 3NNaOH_((aq)) and the tert-butyl alcohol was removed in vacuo. The residuewas dissolved in water and extracted twice with hexanes. The water layerwas acidified with 3N HCl_((aq)) and extracted twice with ether. Theorganic layer was washed with water and brine, dried over Na₂SO₄, andconcentrated in vacuo. The residue was coated on silica gel and purifiedby flash column chromatography (1:9 EtOAc:MeOH) to give(7S,11aS,11bR)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,111a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylicacid (RJ-026) (7.8 mg, 74%) as a white solid. Data for RJ-026: Mp229-231° C.; IR (film): 3448, 2938, 2865, 2837, 1701, 1458, 1440, 1385,1363, 1121, 1104, 1039, 1016, 969 cm⁻¹; ¹H NMR (500 MHz, CD₃OD) δ7.16-7.13 (m, 1H), 3.83-3.80 (m, 1H), 2.93-2.85 (m, 1H), 2.48 (d, J=15.5Hz, 1H), 2.37 (dd, J=15.0 Hz, J=9.0 Hz, 1H), 2.00-1.87 (m, 2H),1.84-1.76 (m, 1H), 1.76-1.65 (m, 2H), 1.65-1.57 (m, 1H), 1.50-1.44 (m,1H), 1.44-1.27 (m, 4H), 1.19 (td, J=13.5 Hz, J=4.0 Hz, 1H), 1.11 (t,J=10.8 Hz, 1H), 0.94-0.89 (m, 1H), 0.88 (s, 3H), 0.87 (s, 3H), 0.85 (s,3H); ¹³C NMR (125 MHz, CD₃OD) δ 171.7, 145.1, 133.3, 71.3, 56.3, 49.6,47.0, 43.2, 40.2, 38.8, 34.4, 34.0, 33.2, 31.1, 28.7, 22.7, 22.3, 20.0,14.5; HRMS (EI) calcd for C₁₉H₃₀O₃ [M]⁺: 306.2195. found: 313.2196.

(15) (6aR,1aR,11bS)-methyl6a-formyl-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-029)

A solution of (6aR,11aR,11bS)-methyl6a-(hydroxymethyl)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(40 mg, 0.11 mmol) in DCM (1 mL) was treated with Dess Martinperiodinane (70 mg, 0.16 mmol), which was added in portions at roomtemperature. After being stirred for 1 h, the mixture was diluted withsaturated aqueous Na₂S₂O₃ (1 mL) and NaHCO₃ (1 mL) were added. Theresulting mixture was stirred vigorously for 30 min and the layers wereseparated. The aqueous phase was extracted with CH₂Cl₂ and the combinedorganic extracts were washed with brine and concentrated under vacuum.The residue was column chromatographied (EtOAc-hexanes, 1:11) to obtain(6aR,11aR,11bS)-methyl6a-formyl-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-029) as white solid (80%).

Characteristic data of RJ-029: mp 86-88° C. IR (film) 2948, 1727, 1693,1645, 1437, 1389, 1366, 1258, 1115, 1064, 733 cm⁻¹. ¹H NMR (400 MHz,CDCl₃) δ 9.84 (d, J=1.0 Hz, 1H), 7.16 (dt, J=6.3, 3.1 Hz, 1H), 3.92-3.80(m, 1H), 3.75 (d, J=6.6 Hz, 3H), 3.54 (d, J=14.2 Hz, 1H), 2.89-2.65 (m,2H), 2.40-2.26 (m, 2H), 1.84-1.70 (m, 2H), 1.68-1.58 (m, 1H), 1.53-1.39(m, 4H), 1.18 (td, J=13.4, 4.3 Hz, 1H), 1.01-0.92 (m, 2H), 0.89 (s, 3H),0.79 (s, 3H), 0.75 (s, 3H). ¹³C NMR (100 MHz, CDCl₃) δ 206.2, 199.6,166.6, 142.6, 125.0, 66.5, 55.4, 52.4, 51.4, 41.6, 38.8, 38.2, 37.6,33.3, 33.2, 31.2, 25.5, 21.3, 18.8, 18.5, 15.2. HRMS (ES−) calcd forC₂₁H₂₉O₄ [(M−H)⁺] 345.2066. found 345.2059.

(18)(9Z,12Z)-(7-hydroxy-6a-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-yl)methyloctadeca-9,12,dienoate(RJ-033)/(9Z,9′Z,12Z,12′Z)-((6aR,7R,11bS)-(7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-6a,9-diyl)bis(methylene)bis(octadeca-9,12-dienoate(RJ-034)

To the linoleic acid (LA) (10.4 mg, 0.037 mmol), DMAP (5.5 mg, 0.44mmol) was added at room temperature, to this,((6aR,7R,11aR,11bS)-7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-6a,9-diyl)dimethanol(12 mg, 0.037 mmol) in CH₂Cl₂ (0.5 mL) was added, stirred and cooled to0° C. and DCC (9 mg, 0.044 mmol) was directly added to the abovemixture. The reaction mixture was stirred at room temperature forovernight and then the mixture was filtered, washed with CH₂Cl₂ (2 mL).The filtrate was successively washed with aq. HCl, sat. NaHCO₃ solutionand then brine. The CH₂Cl₂ layer was dried over Na₂SO₄, concentrated andthe resulting residue was column chromatographied to give(9Z,12Z)-(7-hydroxy-6a-(hydroxymethyl)-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-yl)methyloctadeca-9,12,dienoate (RJ-033) as colorless oil (40%) and(9Z,9′Z,12Z,12′Z)-((6aR,7R,11bS)-(7-hydroxy-4,4,11b-trimethyl-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-6a,9-diyl)bis(methylene)bis(octadeca-9,12-dienoate(RJ-034) as colorless oil (20%).

Characteristic data of RJ-033: IR (film) 3346, 3009, 2925, 2854, 1737,1660, 1646, 1463, 1385, 1169, 1055, 967 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ5.93 (dd, J=8.2, 3.3 Hz, 1H), 5.50-5.24 (m, 4H), 4.44 (s, 2H), 4.21 (d,J=11.4 Hz, 1H), 3.95 (d, J=11.4 Hz, 1H), 3.52 (d, J=8.1 Hz, 1H), 2.77(t, J=6.5 Hz, 2H), 2.66 (dd, J=16.3, 8.7 Hz, 2H), 2.44 (d, J=16.4 Hz,1H), 2.32 (t, J=7.5 Hz, 2H), 2.27 (dt, J=13.2, 3.1 Hz, 1H), 2.16 (dd,J=16.1, 10.2 Hz, 1H), 2.09-1.98 (m, 4H), 1.75 (d, J=12.5 Hz, 1H),1.66-1.54 (m, 8H), 1.47-1.25 (m, 14H), 1.13 (td, J=13.5, 4.3 Hz, 1H),1.04 (tdd, J=13.3, 4.1, 1.5 Hz, 1H), 0.89 (t, J=6.9 Hz, 3H), 0.87 (d,J=3.6 Hz, 3H), 0.85-0.81 (m, 2H), 0.80 (s, 3H), 0.75 (s, 3H). ¹³C NMR(100 MHz, CDCl₃) δ 173.8, 132.6, 132.2, 130.2, 130.0, 128.1, 127.9,79.4, 69.5, 62.7, 56.3, 55.8, 46.4, 41.9, 39.7, 38.4, 34.3, 33.7, 33.5,33.4, 33.2, 31.5, 29.6, 29.3, 29.1, 27.2, 25.6, 25.0, 22.9, 22.6, 21.3,18.6, 18.4, 16.2, 14.1. HRMS (ES+) calcd for C₃₈H₆₄O₄Na [(M+Na)⁺]607.4702. found 607.4695.

Characteristic data of RJ-034: IR (film) 3457, 3007, 2924, 2854, 1737,1659, 1650, 1454, 1385, 1243, 1163, 1087, 1054, 723 cm⁻¹. ¹H NMR (400MHz, CDCl₃) δ 5.91 (d, J=4.7 Hz, 1H), 5.48-5.20 (m, 8H), 4.70 (d, J=11.5Hz, 1H), 4.45 (d, J=12.8 Hz, 1H), 4.43 (s, 2H), 3.43 (t, J=8.1 Hz, 1H),2.77 (t, J=6.5 Hz, 4H), 2.57 (dd, J=16.3, 8.8 Hz, 1H), 2.39 (d, J=16.2Hz, 1H), 2.33 (dd, J=15.3, 7.7 Hz, 4H), 2.10-2.00 (m, 8H), 1.77 (d,J=12.1 Hz, 1H), 1.69-1.57 (m, 4H), 1.44 (d, J=13.9 Hz, 2H), 1.40-1.24(m, 28H), 1.13 (td, J=13.4, 3.9 Hz, 2H), 0.89 (t, J=6.8 Hz, 6H), 0.86(s, 3H), 0.83 (s, 3H), 0.80 (s, 3H).

(22) (±)-(6aR,11aR,11bS)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimet-hyl-7-oxotetradecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-038)

To a solution of (±)-(4aR,4bS,10aR)-methyl10a-((methoxycarbonyloxy)methyl)-4b,8,8-trimethyl-1-oxotetradecahydrophenanthrene-2-carboxylate(RJ-037) (23 mg, 0.058 mmol) in DCE (0.6 mL) was added Et₂Zn (1.0 M inhexane, 93 μL, 0.093 mmol) at 0° C. After 10 minutes, CH₂I₂ (8 μL, 0.093mmol) was added and the mixture was stirred at 0° C. for 2 h. Then thereaction mixture was allowed to warm to room temperature and stirred foranother 14 h. The reaction contents were quenched with sat. NH₄Cl_((aq))(2 mL) at 0° C. and allowed to warm to room temperature. The phases wereseparated, and the aqueous layer was extracted with ether (3×2 mL). Theorganic extracts were combined, washed with sat. NaHCO_(3(aq)) (10 mL)and brine (10 mL), dried over Na₂SO₄, and concentrated in vacuo. Theresidue was purified by flash column chromatography (gradient from0:1→1:1 EtOAc:DCM) to afford (±)-(6aR,11aR,11bS)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimethyl-7-oxotetradecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-038) (16 mg, 61%) as colorless liquid. Data for RJ-038: IR (film)2951, 2868, 2843, 1750, 1704, 1441, 1389, 1367, 1264, 1201, 1175, 1158,1116, 961, 791 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 4.72 (d, J=11.2 Hz, 1H),4.55 (d, J=11.2 Hz, 1H), 3.76 (s, 3H), 3.69 (s, 3H), 2.99 (dd, J=11.6Hz, J=6.8 Hz, 1H), 2.87-2.73 (m, 2H), 2.14-2.04 (m, 1H), 1.84-1.72 (m,3H), 1.72-1.61 (m, 5H), 1.61-1.57 (m, 1H), 1.52-1.42 (m, 1H), 1.42-1.28(m, 2H), 1.28-1.21 (m, 1H), 1.15 (td, J=13.4 Hz, J=4.0 Hz, 1H),0.94-0.89 (m, 1H), 0.87 (s, 3H), 0.87 (s, 3H), 0.81 (s, 3H); ¹³C NMR(100 MHz, CDCl₃) δ 211.2, 175.5, 155.6, 68.5, 56.4, 56.2, 54.8, 54.6,52.1, 41.7, 39.6, 38.7, 38.5, 38.5, 33.4, 33.2, 31.5, 29.4, 21.4, 21.3,18.6, 18.1, 16.0; HRMS (MALDI) calcd for C₂₃H₃₆O₆ [M+Na]⁺: 431.2410.found: 431.2422.

(23) (±)-(6aR,11aR,11bS)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimeth-yl-7-oxo-2,3,4,4a,5,6,6a,7,10,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-039)

To a solution of (±)-(6aR,11aR,11bS)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimethyl-7-oxotetradecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-038) (8.0 mg, 0.020 mmol) in THF (0.2 mL) was added LHMDS (0.5M inTHF, 59 μL, 0.029 mmol) at −78° C. The mixture was allowed to warmslowly to −20° C. over the course of 2 h. Then, cooled down to −78° C.,a solution of PhSeCl (5.6 mg, 0.029 mmol) in THF (0.05 mL) was added at−78° C. After 3 h, the reaction was quenched by sat. NaHCO_(3(aq)) (2mL), and the aqueous layer was extracted with ether (3×2 mL). Theorganic extracts were combined, washed with brine (6 mL), dried overNa₂SO₄, and concentrated in vacuo. To a solution of the residuementioned above in THF (0.4 mL) was added H₂O_(2(aq)) (4 μL, 0.050 mmol)and pyrine (4 μL, 0.050 mmol) at room temperature. After 2 h, thereaction was quenched by sat. NaHCO_(3(aq)) (2 mL), and the aqueouslayer was extracted with ether (3×2 mL). The organic extracts werecombined, washed with brine (6 mL), dried over Na₂SO₄, and concentratedin vacuo. The residue was purified by flash column chromatography(gradient from 1:49→1:9 EtOAc:hexanes) to give(±)-(6aR,1.1aR,11bS)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,10,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-039) (5.0 mg, 63%) as colorless oil. Data for 37: IR (film) 2952,2865, 2845, 1752, 1721, 1693, 1440, 1389, 1363, 1264, 1210, 1134, 965,948 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 6.94 (d, J=2.0 Hz, 1H), 4.70 (d,J=11.0 Hz, 1H), 4.59 (d, J=11.0 Hz, 1H), 3.78 (s, 3H), 3.75 (s, 3H),2.88-2.79 (m, 1H), 2.32-2.21 (m, 1H), 1.96-1.85 (m, 1H), 1.85-1.77 (m,2H), 1.72-1.65 (m, 1H), 1.65-1.42 (m, 4H), 1.42-1.23 (m, 3H), 1.14 (td,J=13.4 Hz, J=4.0 Hz, 1H), 0.97-0.87 (m, 2H), 0.92 (s, 3H), 0.86 (s, 3H),0.81 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ 207.2, 167.5, 155.5, 138.1,137.0, 69.0, 56.2, 55.5, 54.9, 54.9, 52.5, 41.7, 39.3, 38.9, 33.4, 33.2,32.4, 29.5, 21.8, 21.4, 18.5, 18.2, 16.2; HRMS (ESI) calcd for C₂₃H₃₄O₆[M+Na]⁺: 429.2253. found: 429.2254.

(24) (±)-(6aR,11aR)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-40)

A solution of (±)-(6aR,11aR,11bS)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,10,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-039) (25 mg, 0.062 mmol) and DBU (19 μL, 0.124 mmol) in benzene(1.24 mL) was refluxed for 3 h. The reaction was cooled down to roomtemperature and then quenched by sat. NH₄Cl_((aq)) (2 mL). The phaseswere separated, and the aqueous layer was extracted with EtOAc (3×2 mL).The combined organic layers were washed with sat. NaHCO_(3(aq)) (5 mL)and brine (5 mL), dried over Na₂SO₄, and concentrated in vacuo. Theresidue was purified by flash column chromatography (gradient from1:49→1:9 EtOAc:hexanes) to give (±)-(6aR,1.1aR)-methyl6a-((methoxycarbonyloxy)methyl)-4,4,11b-trimethyl-7-oxo-2,3,4,4a,5,6,6a,7,8,11,11a,11b-dodecahydro-1H-cyclohepta[a]naphthalene-9-carboxylate(RJ-40) (20 mg, 80%) as colorless oil. Data for RJ-40: IR (film) 2950,2868, 2843, 1751, 1711, 1645, 1440, 1388, 1367, 1260, 1116, 1069, 963,790 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 7.13-7.09 (m, 1H), 4.75 (d, J=11.2Hz, 1H), 4.63 (d, J=11.2 Hz, 1H), 3.81 (dd, J=13.8 Hz, J=2.2 Hz, 1H),3.74 (s, 3H), 3.73 (s, 3H), 3.58 (d, J=14.0 Hz, 1H), 2.78-2.66 (m, 1H),2.60-2.50 (m, 1H), 2.08-2.01 (m, 1H), 1.86-1.78 (m, 1H), 1.73-1.54 (m,3H), 1.54-1.44 (m, 1H), 1.44-1.23 (m, 3H), 1.16 (td, J=13.4 Hz, J=4.0Hz, 1H), 0.95 (s, 3H), 0.94-0.88 (m, 2H), 0.87 (s, 3H), 0.82 (s, 3H);¹³C NMR (100 MHz, CDCl₃) δ 207.2, 167.0, 155.4, 144.0, 124.4, 69.3,56.3, 55.8, 54.8, 52.2, 52.1, 41.6, 39.8, 38.3, 37.5, 33.7, 33.4, 33.1,26.6, 21.3, 18.5, 18.5, 15.6; HRMS (EI) calcd for C₂₃H₃₄O₆ [M+Na]⁺:429.2253. found: 429.2260.

Example 2 Characterization of Bioactivities of Exemplary GLP-1 ReceptorModulators

Receptor endocytosis following arrestin recruitment and cAMP productionsubsequent to Gαs coupling are two major immediate downstream cellularpathways upon GLP-1 receptor activation. Arrestin recruitment will leadto proliferation and anti-apoptosis of pancreatic b-cells (30, 31),while production of cAMP will lead to insulin secretion (Doyle et al.,Pharmacology & Therapeutics, 2007, 113, 546). In this example, theβ-arrestin2-GFP biosensor technology (45) was employed in screening fora plant extract library to identify those that can potentiate GLP-1 toelicit receptor endocytosis. Upon agonist binding to GPCR, thecytoplasmic arrestin rapidly translocate to and bind to the activatedGPCR. Arrestin also mediates receptor internalization by targeting thereceptor to clathrin-coated pits (46) which is a convergent step of GPCRactivation. β-arrestin2-GFP biosensor technology involved less steps ofenzymatic cascade and yielded more information on the compound (45),thus was used in the initial screening of plant crude extracts and alsoused as an assay for purifying active compounds from plant crudeextracts there would found to be active in eliciting receptorendocytosis. Following the activity of this assay, a Hedychiumcoronarium (HC) extract was identified to potentiate GLP-1 in arrestinmediated GLP-1 receptor endocytosis. Furthermore, compounds wereisolated and purified from HC extract to homogeneity by activitydirected fractionation, one of the active compounds was identified to begalanal B. Abilities of synthetic galanal B and its analogs to modulateGLP-1 dependent cAMP production in RINm5F cells and to modulate GLP-1dependent receptor endocytosis were compared. This analysis revealedthat by modifying structure of galanal B, novel compounds can begenerated that selectively potentiate or suppress GLP-1 in Gαs couplingpathway. Since it is well documented that type II diabetes still retaintheir ability to secret GLP-1 (43,44), it is expected that compoundpositively modulates GLP-1 by increasing the potency of GLP-1 should bepotential drug of choice in anti-diabetics.

Materials and Methods

Extraction of HC Leaves

Dried leaves of HC (2 kg) was minced and extracted with ethanol (20 L)at room temperature with constant stirring for 2 days. The extract wasfiltered off and concentrated to give a residue that was suspended in500 ml of 80% ethanol and partitioned with 500 ml of n-hexane for threetimes. The remaining was concentrated, suspended in 500 ml of water andpartitioned with 500 ml ethyl acetate three times followed by 500 mln-BuOH three times. 7 g of ethyl acetate fraction was chromatographed ona silica-gel column (4.5 cm×21 cm, 180 g MERCK 200-400 mesh silica gel)eluted with 1200 ml of 20% and 1200 ml of 30% hexane-EtOAc each,followed by 1600 ml of 50%, 800 ml of 80% hexane-EtOAc and 800 ml of100% EtOAc, the column was further eluted with 800 ml each of 20% and50% methanol: EtOAc; 200 ml was collected for each fraction.

Chemical Synthesis of Galanal B and its Analogues

Commercially available (±)-sclareolide (3) was selected as the startingmaterial and readily converted, as shown in Scheme 1, to olefin 5 in 68%yield through a two-step protocol (1, 2) and subsequently reduced byLiAlH₄ to afford aldehyde 6 in 90% yield. With considerableoptimization, the subjection of 6 into a solution of ylide 7 in hottoluene efficiently furnished Wittig adduct 8 as a single isomer in 85%yield. The terminal double bond of compound 8 was then epoxidizedselectively by m-CPBA, giving an inseparable mixture of 9 and 10 in aratio of 10:1. When the mixture of epoxides 9 and 10 was subjected toCp₂TiCl₂ and Zn metal (3-7), the Ti(III) species generated in situ wouldreact with oxirane to afford the homolytic cleavage of the moresubstituted C—O bond, giving the more stable tertiary radicalintermediate. Subsequently, the ensuing equatorial addition of the-titanoxyl radical to the nitrile caused the generation of imineradical, which evolved into the corresponding ketone. Compound 11 wasobtained exclusively in 60% yield with trace amount of side productsoriginated from ring opening of oxirane. The structural connectivity of11 was confirmed by single-crystal X-ray diffraction. DIBAL-H reductionof 11 to compound 2 (a mixture of triols 12 and 13) followed byselective oxidation of primary alcohols by TEMPO (8) furnished 1:5 ratioof galanal A and galanal B, which can be separated by columnchromatography and are identical in all respect with authentic samplesisolated from HC plant and the reported data (9, 10).

Compound 2 was synthesized according to the method shown in Scheme 2.

MeNHOMe.HCl (2 equiv.), Me₃Al (2 equiv.), CH₂Cl₂, 0° C. to rt (roomtemperature), 85%. b) SOCl₂ (5 equiv.), pyridine (10 equiv.), CH₂Cl₂,−78° C., 80%. c) LiAlH₄ (2 equiv.), THF, rt, 90%. d) 10 (3 equiv.),toluene, reflux, 85%. e) m-CPBA (2 equiv.), CH₂Cl₂, rt, 85%. f) Cp₂TiCl₂(2.2 equiv.), Zn (6.6 equiv.), THF, rt, 60%. g) DIBAL-H (8 equiv.),CH₂Cl₂, −78° C., 80%. h) TEMPO (0.2 equiv.), NCS (4 equiv.), TBACl (0.2equiv.), NaHCO₃, K₂CO₃, CH₂Cl₂, rt, 70%).

Receptor Endocytosis Assay

U2OS osteosarcoma cell line stably expressing a β-arrestin2:GFP fusionprotein was obtained from Norak Biosciences (now Molecular Devices, partof MDS Inc., Mississauga, Ontario). GLP-1 receptor expression constructwas used to transfect the U2OS cell stably expressing β-arrestin2:GFPfusion protein and to obtain cell line stably co-expressing GLP-1receptor and β-arrestin2:GFP fusion protein. High-content imaging ofreceptor endocytosis in cells was conducted with 0.03 mg/ml of ethanolextract from 2500 edible plant to identify potentiating activity for theGLP-1 dependent GLP-1 receptor endocytosis. Extracts were supplied at aconcentration of 100 mg/ml in 100% DMSO. Three replicate 384-well assaymicroplates were plated with U2OS cells stably expressingGFP-β-arrestin2 fusion protein and the GLP-1 receptor at a density of3,000 cells per well. Aliquots of 2.5 μL of 10× stocks of plant extractin phenol red free MEM containing 1, 0.3, or 0.1 mg/ml of plant extractplus 40 nM of GLP-1 were transferred to each well of the cell assayplate, which contained 22.5 μL of phenol red free MEM. The 3 cell assayplates were incubated at room temperature for 60 min before fixationwith 2% formaldehyde and labeling of the cell nuclei with 5 μg/mL of theDNA-binding dye Hoechst 33342 (Molecular Probes, Eugene, Oreg.) for 1hr. Plates were washed with PBS twice and sealed and could be stored at4° C. The final concentration of the extract in the cell plate was 0.1,0.03 and 0.001 mg/ml, and the final DMSO concentration was 1%.

Bioluminescence Resonance Energy Transfer (BRET) Assay

BRET assays were performed to examine the effect of candidate GLP-1receptor modulators on the intracellular cAMP levels in RINm5F cells (aninsulin-secreting cell line), following routine technology. See, e.g.,Bertrand et al., J. Recept Signal Transduct Res., 2002, 22(1-4):533-541;Barak et al., Mol. Pharmacol., 74(3):585-594 (2008); U.S. Pat. No.8,647,887, and WO1999066324.

Imaging and Analysis

Images and data of the cells were performed according to reportedmethods (51), using an ArrayScan® VTI HCS Reader (Cellomics, Inc.Pittsburgh, Pa.). Appropriate filter sets for detection of the 2fluorophores were used, and the different fluorescent signals wererecorded in 2 different image collection channels of the ARRAYSCAN VTIHCS Reader (i.e., channel 1 contained the blue fluorescent Hoechst33342-labeled nuclear images, and channel 2 contained the greenfluorescent GFP-β-arrestin images). A 20×0.4 numerical aperturemicroscope objective was used for the imaging, 3 fields were imaged perwell, and CELLOMICS's Spot Detector BIOAPPLICATION was used to acquireand analyze the images. For these experiments, the Spot DetectorBIOAPPLICATION used the Hoechst-labeled nuclei to identify individualcells and then automatically counted and analyzed the GFP-labeled spotsassociate with each cell. In addition to the number of spots and the sumof their areas and pixel intensities, the BIOAPPLICATION also reportsproperties of the individual nuclei such as their area. The extent ofreceptor endocytosis response was expressed as % of that elicited by 1μM of GLP-1.

One unit of activity is defined as the activity that will reach 50% ofmaximal response in a well of 384-well plate.

Results

Primary Screening Herb Ethanol Extracts that are Able to PotentiateGLP-1 Signaling

To identify dietary molecules that could potentiate GLP-1 dependentreceptor signaling, an ethanol extract library consisting 2500 edibleplants was screened using β-arrestin2-GFP biosensor technology which isbased on the observation that the β-arrestin2 binding of an activatedreceptor is a convergent step of GPCR signaling (45, 46). By monitoringthe binding of β-arrestin2-GFP to the activated GLP-1 receptor and thefollowing β-arrestin-mediated internalization of the activated receptorsto clathrin-coated pits, a dose dependent activation of GLP-1 receptorby GLP-1 was observed. In addition, these processes can be visualizedfrom its image (52), thus easily exclude false positive hits. As shownin FIG. 1, GLP1 (7-37) activates GLP 1 receptor dependent β-arrestin2translocation in a dose dependent and saturable manner, and the EC₅₀ wasmeasured to be 10 nM of GLP-1. This analysis demonstrated that 4 nM ofGLP1 (7-37) is able to activate GLP-1 receptor to the level of 10 to 20%of the maximal response by 1 μM of the peptide. To screen for extractthat acts as a modulator to potentiate GLP-1 concentration dependentGLP1 receptor endocytosis, 0.1 mg/ml of plant ethanol extract was usedto test its ability to enhance the agonistic effect of 4 nM of GLP-1(7-37) on cells co-expressing GLP-1 receptor and β-arrestin2-GFP. 2500herb ethanol extracts were screened for ability to enhance the GLP-1receptor endocytosis elicited by 4 nM of GLP-1. 25 out of 2500 herbextracts were found to enhance the agonistic activity of 4 nM GLP-1(7-37) from 20% to more than 80% of the maximal response, however, 9 outthese 25 primary hits were false positive as judged by visualizing thecorresponding images. The remaining 16 positive hits were tested fortheir selectivity to potentiate GLP-1 receptor by assaying their effecton PTHR, GIPR and BRS3 signaling. These selectivity tests revealed that11 out these 16 positive hits will also activate PTHR or GIPR or BRS3,thus the remaining 5 plant extracts were found specifically potentiateGLP-1 receptor signaling. 4 out of these 5 plants have been documentedto display hypoglycemic effect or anti-diabetic effect on rodent or onother mammalian species, HC is the only plant has not been reported forits effect on blood glucose excursion. HC ethanol extract was furthersubjected to characterizing its effects on the potency and efficacy ofGLP-1 signaling. As shown in FIG. 2A, GFP-arrestin is evenly distributedin the cytosol of cells stably co-expresses β-arrestin1-GFP and GLP-1receptor when the receptor is at resting stage, addition of 0.06 mg/mlof HC extract alone do not change the distribution of β-arrestin1-GFP,stimulation by 4 nM of GLP-1 leads to low level formation of vesiclescontains (3-arrestin1-GFP and GLP-1 receptor in the cytosol andperinuclear region, much more vesicles of the receptor/β-arrestin1-GFPcomplex was observed if cell co-incubated with 4 nM GLP-1 and 0.06 mg/mlof HC extract. FIG. 2B reveals titration of GLP-1 on GLP-1 receptoractivation responses as % of that stimulated by 1 μM of GLP-1, showingthat activation increased as GLP-1 increased from 1.5 nM and reachedsaturation at 324 nM of GLP-1, revealing that GLP-1 elicits GLP-1receptor endocytosis in a dose dependent and saturable manner. While inthe presence of 0.06 mg/ml ethanol extract of HC, the receptoractivation started with 0.44 nM of GLP-1 and reached saturation at aGLP-1 concentration of 10 nM. Comparison of the dose response data ofGLP-1 titration revealed that EC₅₀ was reduced from 10.7 nM to 3.8 nMand that maximal activation increased from 88.2% to 129% by the presenceof 0.06 mg/ml of ethanol extract of HC. The effect of HC ethanol extractis highly dependent on the concentration of GLP-1, since HC plantextracts alone does not elicit GLP-1 receptor endocytosis, indicatingthat it behaves like a potentiator rather than an agonist on GLP-1receptor. This analysis indicated HC ethanol extract potentiate GLP-1signaling by increasing the efficacy and potency of GLP-1. Further, thepotency of HC extract on GLP-1 signaling was also evaluated. A titrationof HC extract was performed on the receptor endocytosis elicited by 4 nMGLP-1. FIG. 2C revealed the dose-response analysis of the titration ofHC extract on receptor activation by 4 nM GLP-1; 4 nM of GLP-1 alone ledto 20% of receptor activation while as the concentration of HC ethanolextract increased to 0.022 mg/ml the receptor activation increased, andwhen HC increased to 0.2 mg/ml the activation by 4 nM of GLP-1 waspotentiated from 20% to 70%. This analysis revealed that the HC ethanolextract potentiated GLP-1 activity in a dose dependent and saturablemanner with an EC₅₀ for GLP-1 signaling around 0.038 mg/ml and thatmaximal potentiation stimulation up to 70% of that of maximal GLP-1titration. The potentiation effect of HC required the presence of GLP-1as the ethanol extract of HC alone do not elicit any receptorendocytosis and has no effect on the distribution of GFP-arrestin inU2OS cells (FIG. 1A).

Isolation and Purification of Active Components from HC Ethanol Extract

Since extract from HC displayed potent activity on GLP-1 elicitedreceptor endocytosis, the active components was isolated according toits effect to potentiate GLP-1 elicited receptor endocytosis. Solventpartition with hexane, ethyl acetate, butanol, and water revealed thatmost of the activity was recovered in the ethyl acetate fraction (Table1), while little activity was noted in the layer of dH₂O. There is a6-fold increase in the affinity of the fraction to potentiate GLP-1elicited GLP-1 receptor endocytosis in ethyl acetate fraction as theEC₅₀ of the fraction was reduced from 0.045 mg/ml to 0.007 mg/ml. Therecovery of the activity was more than 100% in this step offractionation, indicating some of the negative activity was removed.Chromatography of the ethyl acetate fraction on silica gel resolved into36 fractions, activity assay of each fraction showed a significantactivity was recovered between fraction 4 to fraction 12 (FIG. 3). Theseactive fractions (fraction I) were pooled and subjected to reverse phasesilica gel chromatography and resolved into 106 fractions (FIG. 4).There are 30 fractions showing activity significantly higher than thatof 4 nM GLP-1 alone. Fraction 26 is one of the fractions able topotentiate GLP-1 response from 20% to 40% at a concentration of 0.0002mg/ml and its EC₅₀ to potentiate 4 nM of GLP-1 was measured to beEC₅₀=0.00024 mg/ml, and its potentiation effect is selective for GLP-1but not for PTH (FIGS. 5 A and 5B). Since this fraction displayed puritymore than 90% thus was subjected to structure elucidation, and itsstructure turn out to be galanal B which increase the affinity of GLP-1by 4 folds (FIG. 5 C).

TABLE 1 Partition of ethanol extract of HC EC₅₀ at 4 nM Specific TotalWeight GLP1 Activity Activity HC Fraction (gram) (mg/ml) ^(a)(U/mg)^(b)(U) × 10³ Dried plant 1400 Ethanol extract 209.65 0.045 0.42 × 10³8.8 × 10⁷ Hexane 33.42 0.032 1.25 × 10³ 4.2 × 10⁷ Ethyl acetate 19.30.007 5.71 × 10³ 1.1 × 10⁸ Butanol 28.6 nd nd nd dH₂O 124.6 nd nd^(a)One arbitrary unit is defined as the activity that will induce 50%of maximal response in a well of 384-well plate with a volume of 25 μLfor each well. ^(b)Total activity is obtained by multiplying thespecific activity to the total weight.

Characterization of Galanal B, Compound 1, and Compound 2

Galanal B, Compound 1, and Compound 2 were synthesized as describedabove. Their effects on GLP-1 induced receptor endocytosis wereinvestigated. As shown in FIG. 7, dose response curve of GLP-1 andreceptor endocytosis was left shifted by the presence of 0.003 mg/ml ofthese compounds. The EC₅₀ values and efficacy of galanal B, compound 1,and compound 2 are shown in Table 2 below. These results show that thepotentiating effect of these compounds on GLP-1 dependent receptorendocytosis is highly dependent on the presence of GLP-1 since reducedlevels of GLP-1 resulted in a decrease of the activity. The potentiatingeffects of these compounds are all blocked by GLP-1 receptorantagonist—exendin 9 (FIG. 8), indicating their effects are mediated viaGLP-1 receptor.

TABLE 2 Effect of galanal B, compound 1, and compound 2 on the EC₅₀ andefficacy of GLP-1 to elicit receptor endocytosis GLP-1 Compound 2 +Galanal B + Compound 1 + only GLP-1 GLP-1 GLP-1 EC₅₀ (nM) 8.1 0.80 1.14.8 Efficacy 83.2 82 115.2 106.6 (100%)

GLP-1 receptor is coupled to Gαs and leads to generation of cAMP inpancreatic β cells, to examine if the receptor endocytosis potentiatingactivities of the present compounds will translate into the ability topotentiate cAMP production, the effect of these compounds on the GLP-1induced intracellular cAMP generation in RINm5F cell was tested via aBRET assay, using a cAMP biosensor as known in the art, which monitoredthe bioluminescence energy transferring as intracellular cAMP levelincreased (53). It has been demonstrated that cAMP binding induced aremarkable conformational change of the cAMP sensor expressed in RINm5Fcells and the conformational change was determined by measuring thebioluminescence resonance energy transfer between the donor and acceptorin the cAMP sensor. In the resting stage when the intracellular cAMP isminimal, a large BRET ratio was observed. When cells were incubated withGLP-1 or forskolin, an increase of the intracellular levels of cAMP anda decrease of the BRET ratio were observed. However, this dose responsewas eliminated by the presence of 250 μM of adenylyl cyclase inhibitorMDL 12330A. To analyze the effect of compounds on the GLP-1 elicitedcAMP production, it was examined if the potency of GLP-1 be changed bythe presence of galanal b, compound 1, and compound 2. As shown in FIG.9A, the dose response curve of GLP-1 was left shifted by 2.5 orders ofmagnitude when cells were co-incubated with 0.0025 mg/ml of compound 2and EC₅₀ was reduced from 7.8 nM to 0.0025 nM. The effect of compound 2on GLP-1 elicited cAMP production decreased as GLP-1 concentrationreduced and was diminished when GLP-1 concentration reduced to 0.1 pM,indicating that compound 2 alone is not able to induce cAMP production,but to increase the potency of GLP-1 to stimulate cAMP production. Thepotentiating effect of compound 2 on GLP-1 stimulated cAMP productionwas blocked by the presence of GLP-1 receptor antagonist—exendin 9 (FIG.10A) or by MDL12330A—cyclase inhibitor (FIG. 10B), indicating therequirement of GLP-1 receptor and production of cAMP in the potentiationby compound 2. To measure the affinity of compound 2 to potentiate GLP-1dependent cAMP production, the effect of compound concentration on theenhancement of cAMP production elicited by 3 nM of GLP-1 was titrated.As shown in FIG. 9B, the production of cAMP by 3 nM of GLP-1 increasedas the concentration of compound increased and became saturated as theconcentration of compound 2 reach 0.03 mg/ml. The affinity of compound 2to enhance GLP-1 was determined to be 0.001 mg/ml. Similar dose ofgalanal B did not facilitate GLP-1 to stimulate cAMP production (FIG.9A), galanal B did not significantly affect the dose-response curve ofGLP-1 and cAMP production by 3 nM of GLP-1 was not changed by galanal Bup to 0.04 mg/ml (FIG. 9B). By contrast, compound 1 remarkablysuppresses GLP-1 elicited cAMP production in RINm5F cells and the doseresponse curve of GLP-1 on cAMP production was right shifted by almost 2orders of magnitude, the EC₅₀ was increased from 7.8 to 360 nM (FIG.9A). The affinity of compound 1 on GLP-1 elicited cAMP production wasobtained by analyzing the dependence of compound 1 concentration on thecAMP production elicited by 60 nM of GLP-1. As revealed in FIG. 9C, 60nM of GLP-1 generated cAMP more than 80% of that of saturation dose, asthe concentration of compound 1 increased, the cAMP production reducedand reached bottom saturation at 0.003 mg/ml of compound 1. The affinityof compound 1 for GLP-1 in this assay was measured to be 0.0003 mg/ml.The effect of galanal B, compound 1 and compound 2 on the affinity ofGLP-1 to elicit cAMP production in RINm5F cells are summarized in Table3. To examine if these modulation effects of compound 1 and compound 2is specific for GLP-1, 0.03 and 0.01 mg/ml of these compounds wereincluded in the analysis of dose dependence of GIP and glucagon on cAMPproduction in RINm5F cells. As shown in FIG. 11, compound 1 and compound2 at a concentration of 0.025 mg/ml do not affect the cAMP productionelicited by GIP or glucagon, indicating their modulation effects arespecific for GLP-1. The above studies revealed that galanal B, compound1, and compound 2 are modulator without intrinsic agonistic orantagonistic activity, their actions are dependent on both GLP-1 andGLP-1 receptor.

Discussion

TABLE 3 Effect of compound 1, 2, and galanal B on the affinity of GLP-1dependent cAMP production in RINm5F cells GLP-1 Compound 1* + Compound2* + Galanal B* + only GLP-1 GLP-1 GLP-1 EC₅₀ (nM) 7.86 365 0.0025 4.93*Titration of GLP-1 on the production of cAMP in RINm5F cells with 0.003mg/ml of the indicated compounds.

Plants remain either the source of or the inspiration for a significantproportion of the new small-molecule chemical entities. GLP-1 receptormediated signaling is a major target for treatment of type 2 diabetes,further its role in Alzheimer's disease and psoriasis is under clinicalinvestigation. Currently GLP-1 therapeutics are GLP-1 analogs orcompounds with agonistic activity which may cause serious adverse effectupon chronic use. In an attempt to find compound that function as aGLP-1 modulator, instead of agonist, HC plant was identified thatdisplays positive modulating action on GLP-1 elicited receptorendocytosis which requires the presence of GLP-1, indicating theidentified activity functions as a GLP-1 potentiator with littleintrinsic agonistic activity. After activity directed fractionation andpurification, the structure of one of the active compounds was found tobe galanal b. The purified galanal b displayed potent activity topotentiate GLP-1 to elicit recruiting β-arrestin2 to GLP-1 receptor andthe following receptor endocytosis. This activity of galanal b isspecific for GLP-1 as it did not show similar effect on PTH and itscognate receptor. The effect is highly dependent on the presence ofGLP-1 and is abolished by the presence of GLP-1 receptor antagonistexendin 9. To confirm this activity of purified galanal B, galanal B andits modified analogs were synthesized, followed by characterizing theirability (galanal b, compound 1, and compound 2) with respect topotentiating GLP-1 in eliciting receptor endocytosis and in stimulatingcAMP production.

Though galanal b, compound 1, and compound 2 are all able to potentiateGLP-1 to elicit receptor endocytosis in a GLP-1 and GLP-1 receptordependent manner, their ability to modulate GLP-1 in stimulating cAMPproduction is quite distinct, in that compound 1 selectively reduce theaffinity of GLP-1 by a factor of 50, galanal b is neutral, whilecompound 2 selectively potentiate the affinity of GLP-1 up to 1000 fold.This finding demonstrates that compound 1 negatively modulate GLP-1induced cAMP production pathway while compound 2 positively modulate thesame pathway, though they display comparable activity on GLP-1 elicitedreceptor endocytosis. It was demonstrated that these activities andselectivity are dependent on the GLP-1, GLP-1 receptor and specific forthe GLP-1 signaling, as they are GLP-1 concentration dependent, are allblocked by GLP-1 receptor antagonist exendin 9 and do not affect cAMPproduction elicited by the other incretin GIP or by glucagon. Galanal b,compound 1, and compound 2 share similar scaffolds but are structurallydistinct, the present disclosure identifies a critical chemical space ofgalanal b relevant to its selectivity in modulating GLP-1 receptorcoupling efficiency to its intracellular receptor signaling pathway. Thepresent data show that galanal b, compound 1, and compound 2 can displayquite distinct effect on the coupling efficiency of GLP-1 receptor toGαs while display similar effect on the coupling efficiency toβ-arrestin2. The simplest explanation for this observation is that eachcompound will dictate a unique conformation of receptor-GLP-1-compoundcomplex, thus the conformation of GLP-1 receptor is highly dependent onwhether galanal b, compound 1, or compound 2 is in the complex. This isconsistent with the finding that GPCR can exist in multiple activeconformations, distinct conformation of the receptor is stabilized bydistinct ligand structure and may lead to distinct signaling selectivity(55). The present findings raise question as how galanal b and itsanalogs share similar structure but stabilize quite distinctconformation of GLP-1 receptor which coupled comparably to β-arrestin-2but display opposite coupling efficiency to the pathway of cAMPproduction. There are at least two possible mechanisms to account forthese observations. The first explanation is that the compound may bindto and modify the structure of GLP-1 receptor such that manifest as apathway-dependent change in the signaling capacity upon binding to itsorthosteric ligand GLP-1. By binding to and modifying structuralconformation of the receptor, the allosteric inhibitor of parturition(PDC 113.824) induces biased signaling when an orthosteric ligand isco-bound to the prostaglandin F2α receptor (56). Alternatively, thesecompounds bind to GLP-1 to form a complex with distinct conformationwhich will stabilize a distinct set of receptor conformation uponbinding and leads to positively or negatively modulate couplingefficiency to Gαs pathway while display similarly the couplingefficiency to β-arrestin2 mediated receptor endocytosis. Subtleconformation changes in peptide agonists can lead to selective couplingof the receptor to its downstream signaling pathway. As it has beenshown in the case of biased agonist for the type 1 parathyroid hormonereceptor (PTH1R) (25) and angiotensin II type 1A receptor ligands (57),subtle structure change of the peptide ligands can profoundly stabilizea distinct conformation of the receptor protein that selectively affectsthe coupling efficiency of a particular downstream signaling pathway.Two preliminary observations in the present communication are consistentwith the second mechanism that requires the binding of these compoundsto GLP-1 peptide to stabilize compound-GLP-1 complex in a distinctconformation different from that of free GLP-1. First, free GLP-1peptide is quickly degraded by limited trypsin digestion, while galanalb protects GLP-1 from trypsin degradation. Furthermore, compound 2potentiates GLP-1 to stimulate cAMP production in RINm5F cells, but haslittle effect on cAMP production by a small molecule agonist Boc5,though 1000 fold higher of Boc5 is needed to stimulate low level cAMPproduction in RINm5F cells.

The chronic administration of glucagon-like peptide-1 (GLP-1) analogswidely used to treat type-2 diabetes was associated with a potentialrisk of pancreatitis (37-41) or pancreatic/thyroid cancers (42), thoughwith benefits far outweighing the potential risks (58). Physiologically,plasma level of GLP-1 is stringently controlled by ingestion of food andby DPP-4, the plasma level of active GLP-1 will be raised from 5 pM to20-25 pM 15 min after glucose challenge and return to basal level 2 hrlater. However, a constant high plasma concentration of GLP-1 analogs intype 2 diabetes receive GLP-1 analogs therapy (59,60) leads tostimulating target tissues constitutively and may cause the adverseundesired consequences reported in the literatures. Compound 2 whichpotentiate GLP-1 dependent cAMP production by 1000 fold in RINm5F cellsis a “true” positive modulator for GLP-1 because it lacks intrinsicagonistic activity as it does not elicit cAMP production in the absenceof GLP-1. GLP-1 positive modulator function as a dimmer switch thatamplifies the signaling depends on the plasma level of endogenous GLP-1,the intensity of activation of GLP-1 receptor is controlled by thephysiologic concentration of GLP-1 secreted from intestine, thus willnot stimulate target tissues constitutively. Since GLP-1 secretion intype 2 diabetes is comparable to or slightly defective as compare tohealthy subject (43,44), GLP-1 positive modulator will be a potentialcompound to treat type 2 diabetes in the future. Positive modulatorwithout intrinsic agonistic activity but only function to potentiate theactivity of endogenous GLP-1 is expected to overcome the undesiredeffects by skipping the step of constitutive stimulation of the targettissues (58) associated with the chronic administration of GLP-1analogs.

GLP-1 receptors are also expressed in extra-pancreatic tissues, andtrial data suggest GLP-1RAs also have effects beyond their glycaemicactions. GLP-1 signaling has been shown to be potential target for thetreatment of immune dysfunction (Ahern et al., J Eur Acad DermatolVenereol. 2013 November; 27(11):1440-3) (15), neurodegenerative diseasesand cardiovascular disorders (Seufert et al., Diabetes Obes Metab. 2013Dec. 24. doi: 10.1111/dom.12251; Egefjord et al., Dan Med J. 2012October; 59(10):A4519). Biological effects triggered by GLP-1 receptoroften result from the activation of multiple intracellular signalingpathways. Deciphering which signaling pathways are engaged followingGLP-1 receptor activation appears to be primordial to reveal theircontribution in the physiological and pathological processes. Thedevelopment of pathway selective GLP-1 modulators to elucidate the roleof the different signaling mechanisms mediated by GLP-1 receptoractivation may allow the generation of new therapeutic agents withimproved efficacy and reduced side effects. In this regard, theidentification of GLP-1 modulator selectively promoting insulinsecretion without inducing pro-inflammatory effects would offertherapeutic benefit. For many GPCR targets, the required spectrum ofsignaling needed to attain optimal therapeutic benefit is currentlyunknown, which limits the rational selection of drug candidates.Therefore, drug discovery at these tractable targets is considerablychallenging. There are evidences showing that many adverse side effectscan be avoided with such pathway selective compounds and provideimproved treatments. The angiotensin II type 1A receptor, theβ-arrestin-biased ligand Sar1, D-Ala8 angiotensin II (TRV120027) hasbeen shown to increase cardiac performance in anesthetized rats, whereasunbiased ligands reduce cardiac performance. There is also potential forimproved PTH receptor agonists used for the treatment of osteoporosis.The β-arrestin-biased ligand (D-Trp12,Tyr34)-PTH(7-34) stimulatesβ-arrestin while blocking G-protein signaling and promotes anabolic boneformation in the absence of bone resorption. Screening signaling pathwayselective compounds provides considerable scope for the identificationof compounds that selectively target clinically useful GLP-1 signalingpathways and are more neutral or even block alternative pathways, whichgive rise to undesirable side effects. Given the risk of chronic usageof GLP-1 agonist in type 2 diabetes and potentially in other disorders,creating small molecules which modulates GLP-1 signaling pathwayselectivity in a potent unique manner, may dramatically accelerate therate at which critical pathway are selected.

Other Embodiments

All of the features disclosed in this specification may be combined inany combination. Each feature disclosed in this specification may bereplaced by an alternative feature serving the same, equivalent, orsimilar purpose. Thus, unless expressly stated otherwise, each featuredisclosed is only an example of a generic series of equivalent orsimilar features.

From the above description, one skilled in the art can easily ascertainthe essential characteristics of the present disclosure, and withoutdeparting from the spirit and scope thereof, can make various changesand modifications of the present disclosure to adapt it to varioususages and conditions. For example, compounds structurally analogous thecompounds described herein of this present disclosure also can be made,screened for their anti-cancer activities, and used to practice thispresent disclosure. Thus, other embodiments are also within the claims.

All publications and patent applications cited in this specification areherein incorporated by reference as if each individual publication orpatent application were specifically and individually indicated to beincorporated by reference for the purposes or subject matter referencedherein.

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1. A compound of Formula (I):

or a pharmaceutically acceptable salt thereof, wherein: G_(A) is hydrogen, ═O, ═S, —OR″, —SR″, —N(R″)₂, alkenyl, alkynyl, an amide group, an ester group, a phosphate group, an aldehyde group, a nitrile group, an imino group, a ketone group, a thione group, an isonitrile group, an isothiocyanide group, a carbamate group, a thiocarbamate group, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms, wherein each instance of R″ is independently hydrogen, a cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 16 carbon atoms; R_(A1), R_(A2), R_(A3), R_(A4), R_(A5), R_(A6), R_(A7), R_(A8), R_(A9), and R_(A10) are each independently hydrogen, halogen, —OR″, —N(R″)₂, a carboxyl group, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbons, or R_(A1) and R_(A2) are joined to form ═O, or R_(A3) and R_(A4) are joined to form alkenyl; R_(A11), R_(A13), R_(A15), and R_(A17) are each independently hydrogen, halogen, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms; R_(A12), R_(A14), and R_(A16) are each independently halogen, —N(R″)₂, —SR″, —OR″, alkyl, alkenyl, alkynyl, an amide group, a carboxyl group, an ester group, an aldehyde group, a nitrile group, an imino group, a ketone group, a thione group, an isonitrile group, an isothiocyanide group, a urea group, a carbamate group, or a thiocarbamate group, or R_(A14) and R_(A15) are joined to form ═O or ═S; R_(A20) is hydrogen, halogen, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms; and R_(A21) is hydrogen, halogen, —N(R″)₂, —SR″, —OR″, —CH₂OR″, alkenyl, alkynyl, an amide group, a carboxyl group, an ester group, an aldehyde group, a nitrile group, an imino group, a ketone group, a thione group, an isonitrile group, an isothiocyanide group, a carbamate group, a thiocarbamate group, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms; provided that: (i) at least one of R_(A1), R_(A2), R_(A5), R_(A7), R_(A8), R_(A9), R_(A10), R_(A11), R_(A12), R_(A13), R_(A15), R_(A16), and R_(A17) is not hydrogen; (ii) at least one of R_(A3), R_(A4), and R_(A6) is not —CH₃; or (iii) when R_(A21) is —CHO and G_(A) is —OH or ═O, R_(A14) and R_(A15) are each not —CHO.
 2. The compound or pharmaceutically acceptable salt of claim 1, wherein: G_(A) is hydrogen, ═O, ═S, —OR″, —SR″, —NR″H, alkenyl, alkynyl, an amide group, an ester group, an aldehyde group, a nitrile group, an imino group, a ketone group, a thione group, an isonitrile group, an isothiocyanide group, a carbamate group, a thiocarbamate group, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms, wherein each instance of R″ is independently hydrogen, a cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 16 carbon atoms; R_(A1), R_(A2), R_(A3), R_(A4), R_(A5), R_(A6), R_(A7), R_(A8), R_(A9), and R_(A10) are each independently hydrogen, halogen, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbons; R_(A11), R_(A12), R_(A13), R_(A15), R_(A16), and R_(A17) are each independently hydrogen, halogen, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms; R_(A14) is halogen, —NR″H, —SR″, —OR″, alkenyl, alkynyl, an amide group, an ester group, an aldehyde group, a nitrile group, an imino group, a ketone group, a thione group, an isonitrile group, an isothiocyanide group, a carbamate group, or a thiocarbamate group; R_(A20) is hydrogen, halogen, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms; and R_(A21) is hydrogen, halogen, —NR″H, —SR″, —OR″, alkenyl, alkynyl, an amide group, an ester group, an aldehyde group, a nitrile group, an imino group, a ketone group, a thione group, an isonitrile group, an isothiocyanide group, a carbamate group, a thiocarbamate group, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms.
 3. The compound or pharmaceutically acceptable salt of claim 1, wherein the compound is of Formula (I-A), (I-A1), (I-B), or (I-C):

4-6. (canceled)
 7. The compound or pharmaceutically acceptable salt of claim 1, wherein G_(A) is ═O, ═S, —SR″, —OR″, —N(R″)₂, —OH, —SH, or —NH₂.
 8. (canceled)
 9. The compound or pharmaceutically acceptable salt of claim 1, wherein R_(A6) is acyclic, substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl.
 10. (canceled)
 11. The compound or pharmaceutically acceptable salt of claim 1, wherein R_(A14) is an ester group, an aldehyde group, a ketone group, alkyl, a carboxyl group, or a urea group.
 12. (canceled)
 13. The compound or pharmaceutically acceptable salt of claim 1, wherein R_(A21) is hydrogen, —CH₂OR″, an aldehyde group, or substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl. 14-16. (canceled)
 17. The compound or pharmaceutically acceptable salt of claim 1, wherein the compound is of the formula:

or a pharmaceutically acceptable salt thereof, wherein


18. A compound of Formula (II):

or a pharmaceutically acceptable salt thereof, wherein: G is hydrogen, ═O, ═S, —NR′H, —SR′, or —OR′, wherein R′ is hydrogen, an ester group, a ketone group, a thione group, or a cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 16 carbon atoms; W is —O—, —S— or —NR′—; X and Y are each independently a single bond or a saturated or unsaturated, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 3 carbon atoms; R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₂ and R₁₃ are each independently hydrogen, halogen, or a cyclic or acyclic, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms, or R₂ and R₃ may join to form cycloalkyl, heterocycloalkyl, aryl, or heteroaryl; R₁₀ and R₁₁ are each independently hydrogen, halogen, an amino group, an amide group, an ester group, an aldehyde group, a nitrile, an imino group, a ketone group, a thione group, an isonitrile group, an isothiocyanide group, a carbamate group, a thiocarbamate group, or a cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1 to 6 carbon atoms; R₁₄ is hydrogen or a saturated or unsaturated, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1-16 carbon atoms; R₁₅ is hydrogen or a saturated or unsaturated, substituted or unsubstituted, branched or unbranched, (hetero)aliphatic group having 1-6 carbon atoms; and R₂₁ is

 or an aldehyde group; provided that: (i) at least one of R₄, R₅, R₆, R₇, R₈, R₉, and R₁₀ is not hydrogen; (ii) R₁ is not —CH₃; or (iii) when R₂₁ is —CHO and G is —OH or ═O, R₁₁ is not —CHO.
 19. The compound or pharmaceutically acceptable salt of claim 18, wherein the compound is of Formula (II-A), (II-B), or (II-C):

20-21. (canceled)
 22. The compound or pharmaceutically acceptable salt of claim 18, wherein R₂₁ is

—CH₂OH, or an aldehyde group. 23-24. (canceled)
 25. The compound or pharmaceutically acceptable salt of claim 18, wherein G is ═O or —OR′.
 26. (canceled)
 27. The compound or pharmaceutically acceptable salt of claim 18, wherein W is —O—, X is methylene, or Y is methylene. 28-29. (canceled)
 30. The compound or pharmaceutically acceptable salt of claim 18, wherein R₁₁ is an ester group, an aldehyde group, a ketone group, or acyclic, substituted or unsubstituted, branched or unbranched, C₁₋₆ alkyl.
 31. A pharmaceutical composition comprising a compound or pharmaceutically acceptable salt of claim 1, and a pharmaceutically acceptable carrier.
 32. A method for regulating blood glucose level in a subject, comprising administering an effective amount of the pharmaceutical composition of claim 31 to a subject in need thereof.
 33. The method of claim 32, wherein the subject has, is suspected of having, or is at risk for a disease or disorder selected from the group consisting of type I diabetes, type II diabetes, gestational diabetes, obesity, excessive appetite, insufficient satiety, and a metabolic disorder.
 34. A method for activating a glucagon-like peptide 1 (GLP-1) receptor in a subject in the presence of GLP-1, comprising administering to a subject in need thereof an effective amount of the pharmaceutical composition of claim
 31. 35. A pharmaceutical composition comprising a compound or pharmaceutically acceptable salt of claim 18, and a pharmaceutically acceptable carrier.
 36. A method for regulating blood glucose level or activating a glucagon-like peptide 1 (GLP-1) receptor in a subject, the method comprising administering to a subject in need thereof an effective amount of the pharmaceutical composition of claim
 35. 